电感性本质安全电路L/R的选择原则

基于电感性本质安全电路放电电流线性衰减模型,引入最小建弧电压的概念,得到了放电时间不含未知参数的表达式,利用电感电路的本质安全性能判别式,确定了电感电阻比L/R的选取原则.     

VARIABLE DISCHARGE TYPE CURVE SOLUTIONS FOR CONFINED AQUIFERS1

ABSTRACT: Almost all of the existing solutions of aquifer test analysis assume constant discharge rate boundary conditions. In many actual pumping tests, constant discharge cannot be maintained. This paper presents a general solution for an aquifer test with variable discharge. The exact solution of drawdown distribution around an infinitesimally small diameter well in a uniform, horizontal, extensive, homogeneous, and isotropic confined aquifer is presented when the discharge changes with time during the aquifer test period. A general equation for the type curves resulting from any discharge variability is given, and its application for the exponential changes is presented in detail. A simple straight line procedure is proposed for field applications by considering late time drawdown data. The consideration of constant discharge leads to overestimation of transmissivity but storativity is underestimated. Practical application of the discharge variability is illustrated by a field example.     

AVERAGE DISCHARGE,PERENNIAL FLOW INITIATION,AND CHANNEL INITIATION ‐ SMALL SOUTHERN APPALACHIAN BASINS1

ABSTRACT: Regional average evapotranspiration estimates developed by water balance techniques are frequently used to estimate average discharge in ungaged streams. However, the lower stream size range for the validity of these techniques has not been explored. Flow records were collected and evaluated for 16 small streams in the Southern Appalachians to test whether the relationship between average discharge and drainage area in streams draining less than 200 acres was consistent with that of larger basins in the size range (> 10 square miles) typically gaged by the U.S. Geological Survey (USGS). This study was designed to evaluate predictors of average discharge in small ungaged streams for regulatory purposes, since many stream regulations, as well as recommendations for best management practices, are based on measures of stream size, including average discharge. The average discharge/drainage area relationship determined from gages on large streams held true down to the perennial flow initiation point. For the southern Appalachians, basin size corresponding to perennial flow is approximately 19 acres, ranging from 11 to 32 acres. There was a strong linear relationship (R²= 0.85) between average discharge and drainage area for all streams draining between 16 and 200 acres, and the average discharge for these streams was consistent with that predicted by the USGS Unit Area Runoff Map for Georgia. Drainage area was deemed an accurate predictor of average discharge, even in very small streams. Channel morphological features, such as active channel width, cross‐sectional area, and bankfull flow predicted from Manning's equation, were not accurate predictors of average discharge. Monthly baseflow statistics also were poor predictors of average discharge.     

云应地区制盐行业废水零排放的可行性论证与实施方案

根据井矿盐生产工艺特点及云应地区实际，分析了冲渣除尘水、冷却水和工艺废水循环使用的可能性，论证了云应地区制盐行业实现废水零排放的可行性，并提出了实现零排放的具体建议。     

城市建设的环境破坏分析及对策框架

随着城市经济的飞速发展，城市建设对环境的破坏日趋严重，本文分析了城市建设中环境破坏的种种类型和环境破坏的根源，提出了以环境规划为先导，排污总量控制为目标，环境监督管理为重点，法律，行政，经济和教育手段的环境对策框架。     

受限空间脉冲细水雾灭火数值模拟

为研究脉冲细水雾灭火效果和灭火机理,采用FDS软件对连续和脉冲细水雾熄灭受限空间油盘火进行了数值模拟。通过模拟和理论分析确定了脉冲细水雾周期为8 s开启、8 s暂停,并设置了冷却和窒息两种灭火条件,对两种细水雾熄灭不同尺寸的柴油池火进行了研究。结果表明:连续细水雾无法熄灭直径15 cm和20 cm的小尺寸油盘火,对直径25 cm中尺寸油盘火的灭火机理为冷却,对直径为30cm和35 cm大尺寸油盘火的灭火机理为窒息;脉冲细水雾能够熄灭不同尺寸的油盘火,且灭火效率高,火焰熄灭均发生在喷头暂停喷水期间,灭火机理为水雾蒸发稀释氧气而窒息。     

Investigations on removal of SO2 from flue gas by aerosol formation in pulsed corona discharge process

The removal of SO₂ from flue gas by pulsed corona discharge in presence of ammonia was experimentally investigated. The results showed that the SO₂ removal mainly depends on thermal reaction of SO₂ with NH₃ and enhancements of 0%—25% by pulsed corona discharge in the range of the specific energy 0—5 Wh/Nm³. The aerosol mass concentration, mainly composed of ammonium sulfate, increased with specific energy dissipated into the reactor. With an initial concentration of 2000—2100 ppmv SO₂ and energy consumption of 3 Wh/Nm³, when a stoichiometric amount of ammonia is injected, the removal efficiency of SO₂ and percentage of ammonium sulfates in reaction products are all ≥80%. The collection efficiency of the reactor for aerosol is about 74% at a flue gas temperature of 60 to 65℃ and a water vapor content of 9% to 11% volume.     

采用分级配风燃烧器降低 NOx排放

二甲苯塔底再沸炉采用引进的分级配风燃烧器。对分级配风燃烧器的结构、性能及使用过程中存在的问题做了详细的分析。通过与国产化改进后喷嘴的性能比较，说明了改造是成功的，节约了设备采购费用和操作费用，烟气中NOx含量远低于要求的排放标准。     

小排放量印花废水处理工程实例分析

介绍了采用电解絮凝气浮工艺处理小排放量的印花废水的工程实例,该工艺具有运行稳定、操作简单、运行费用低的特点.     

沈阳市实施总量控制与排污许可证制度的探讨

文中阐述了沈阳市总量控制工作进展的基础上，针对目前无序排放污染物的混乱局面，讨论有效的治理方案，并进一步提出沈阳市实行总量控制、排污许可证和排污交易的方法和步骤。