ATMOSPHERIC CONTROLS OF WATER EXCHANGE IN GREAT LAKES BASIN1

ABSTRACT Existing meteorological controls of water exchange by precipitation and evaporation on the Great Lakes are almost entirely inadvertent and related to man's urban-industrial complexes and their effect upon precipitation processes. These inadvertent effects have led to 10 to 40% increases in precipitation in localized areas within the basin. Envisioned growth of urban-industrial complexes within the Great Lakes region should lead to more inadvertent weather modification in the Basin. The only existing planned weather modification efforts are those at Lake Erie which are attempting to eliminate by redistribution the concentration of lake-derived heavy snowfall along the south shore. It appears reasonable to assume that practical increases of lake precipitation on the order of 5-20% could be achieved on an operational basis over the Great Lakes in the next 10 years, but the time of accomplishment will depend on national priorities, international cooperation, and economic factors. These activities would certainly produce a sizeable increase in the water quantity of the Great Lakes and should result in an improvement in water quality. Operational methods of evaporation suppression applicable to the lakes are just not available. Meteorological controls to ameliorate certain undesirable lake-effect snowstorms are a near reality.     

大空间火灾实验中温度测量的误差分析

在大空间火灾实验中，由于测温系统的庞大和复杂，导致影响温度测量的误差因素增多。该文主要从热电偶测温误差理论分析入手，讨论全尺寸火灾实验温度测量误差的因素和大小，阐述了大空间烟气温度测量的误差引入方式和减少误差的措施，并对一组大空间内火灾机械排烟实验的温度数据进行了误差分析。     

浅谈环境成本

本文论述了环境的资源观、价值观以及环境的商品性,介绍了环境成本概念,分析了环境成本确认、环境成本的核算。     

澜沧铅矿井下有毒有害气体测评与控制

通过对井下作业点空气中CO、SO2、H2S、NO2和CO2等有毒有害气体的测定,将测定结果与进行比较,发现澜沧铅矿井下部分作业地点空气中CO、NO2和CO2浓度超过规定标准.根据分析、评价的结果,结合该矿实际情况,提出了控制井下有毒有害气体、改善井下空气质量的通风排毒等技术措施,以及防止井下有毒有害气体中毒的管理和个体防护措施.通过实施这些措施,使澜沧铅矿井下有毒有害气体得到了有效控制,其浓度达到了规定的要求.     

监测技术在深基坑地下连续墙工程中的应用

随着城市建设的发展，采用地下连续墙作为深基坑围护结构的深基础工程越来越多，它以其墙体刚度大，阻水性能好，一墙多用，并能适应多种地层条件而广泛应用于高层建筑的地下室等基础结构物的建造，本结合广州市粤财大厦地下连续墙工程，就其监测内容及监测结果进行了详细分析，结果表明，本基坑围护结构体系是安全的，达到了基坑开挖与围护工程安全与稳定的要求，对类似工程具有指导和借鉴意义。     

CHANNEL DISCHARGE MEASUREMENT BY THERMODILUTION1

ABSTRACT: An investigation was conducted to determine the feasibility of applying thermodilution technology to discharge measurements in small open channels. A series of tests were performed in which the time-temperature dilution curves were recorded and analyzed. The independent variables included the channel discharge, the injectate drop height, the volume of tracer, and the mixing distance. Flows ranged from 0.67 cfs to 2.45 cfs with Froude numbers less than 0.30. The results indicated that the thermodilution technique is a feasible method for discharge measurement. It was determined that a heat content, 1°, of 40°C provides a design criteria in which the mixing distance was related to the flow depth and discharge in a rectangular channel. An empirical expression was derived to determine the approximate mixing distance as a function of the flow depth.     

开发田林八渡笋资源的前景与措施

田林县八渡笋资源丰富，本文分析了田林的生态环境，开发八渡笋的有利条件、经济效益、发展前景和开和利用的措施。     

Study of the Determination of the Ultimate Aerobic Biodegradability of Plastic Materials Under Controlled Composting Conditions

Several ISO standards for determining the ultimate aerobic/anaerobic biodegradability of plastic materials have been published. In particular, ISO 14855-1 is a common test method that measures evolved carbon dioxide using such methods as continuous infrared analysis, gas chromatography or titration and others (ISO 14855-1(2005.9)). This method is a small-scale test for determining the ultimate aerobic biodegradability of plastic materials, where the amounts of compost inoculum and test sample in one tenth comparing with that of ISO 14855-1. This method is well versed in ISO/DIS 14855-2 which the carbon dioxide evolved from test vessel is determined by gravimetric analysis of carbon dioxide absorbent. The focus of this study is to elucidate statistically the results of round robin test by seven countries used MODA, which were various deviations among the experiments.     

职业噪声暴露测量方法探讨

噪声暴露是声压级与作用时间的综合结果。出于对听力保护的目的,积极推行声暴露的测量方法十分必要。本文通过对等效连续A计权声级、噪声暴露量、噪声剂量的测量和换算提出了对现行标准的理解和应用。     

中信广场风场特性及风致结构振动的同步监测

通过对广州中信广场在台风“达维”作用下其风场与风致结构振动的现场同步监测，获得了台风风场和结构动力特性，及风致结构振动响应等相关结果。通过对现场测试数据的分析，验证了湍流强度随平均风速增大而减小和阵风因子随湍流强度增大而增大等规律，实测的脉动风速谱与von Karman谱亦很吻合。同时通过对中信广场加速度响应与平均风速关系分析得出，该高层建筑物的顶部风速即使处于低中风速范围时，其横风向响应已接近于顺风向响应。根据实测风振加速度数据，对结构动力特性（频率及阻尼比）进行了识别，采用随机减量方法求得了结构在两个主轴方向第一振型阻尼比与振幅的非线性关系。