Water model study on flow optimization of five streams L-type tundish

In this paper, the water model method is used to optimize the flow behavior of asymmetrical five streams L-type tundish in a steelmaking plant. The results show that the optimization plan is set up with turbulence suppressor T+ vice guide wall D2+ main guide wall with three holes (D1a) which consists of top two holes with 25° inclination and one hole with 30° inclination below. With this plan, the time which the colorants reach to the outlets increases, the difference of response time in all outlets decreases, the peak concentration of the RTD reduces, the existence time of high concentration liquid steel extends, and the ratio of dead zone in each streams reduces.     

Sampling Investigation on Inhatitant Domestic Tap Water Consumption Situation and It’s Characteristics Analysis

Economics.Through sampling investigation and analysis on inhabitant domestic tap water consumption situation,it is given that economic factors are the main factors influence inhatitant's water consumption.The functional relations among inhabitant's income and water consumption,water price and consumption are given. The tap water's income elasticity of demand and price elasticity of demand is analyzed, along with the fluctuating range month by month of inhabitant's water consumption.Finally ,this paper offers the reference data for planning the ability of water supply and making policies of ladder water prices.     

Application of Water Quality Standand Leuel Method in Eualuazing Status Quo of Heauy-Metals Pollution in Riuers

The status quo of heauy-metals pollution in water phase of course of Long-Tan hydropower statian was eualuated by water Quality Standand Level Method. With this special method,mone objectiue and definite results were obtained.     

Preliminary Study on Eco-environmental Water Demand in Taohuajiang Valley, Guilin

Eco-environmental water demand in Taohuajiang Valley of Guilin is defined as the minimum water volume required by the valley to maintain the eco-environmental quality not to be degraded over time.By using the site survey data,the eco-environmental water demand in Taohuajiang valley is studied preliminarily.The results calculated indicate that: the out-stream eco-environmental water demand is about 14.9 million m3 per year,about 4 percent of annual runoff of the valley;and the in-stream eco-environmental water requirement is about 109.8 million m3 per year,about 30 percent of annual runoff.This study provides scientific basis for local sustainable water resources use and management as well as for eco-environmental water requirement study in similar regions in terms of Karst geological condition and climate.     

土壤水分对稻米外观品质的影响

水稻的分蘖期、长穗期、抽穗后1～10d、11～20d、21～30d及1～30d,用负压式土壤湿度计监测,分别进行土壤水势为-30～-35kPa、-60～-65kPa的控水处理,收获后对优势粒、中位粒、劣势粒进行粒形和垩白测定,发现在不同土壤水分下S品种长穗期和抽穗后1～10d控水显著抑制了籽粒伸长,也不同程度的抑制了籽粒增宽和长厚,以S4处理受抑制的程度最为严重;Y品种主要是长穗期控水显著抑制了粒长、粒宽和粒厚;两品种的多数处理不同程度的提高了粒厚,这在优势粒中更明显;土壤水分对粒长/宽的影响很小。S品种各处理垩白率、垩白度多低于CK,Y品种各处理垩白率、垩白度多高于CK。对两个品种来说长穗期是影响外观品质的主要水分敏感期,节水栽培应从品种选择入手。     

黄土高原北部垄膜沟植田间集雨高效栽培技术研究

在黄土高原北部,采用起垄覆膜(垄上覆膜种植马铃薯,垄沟种植谷子)的垄沟间作田间集雨补灌栽培并结合增施氮、磷、钾化肥,具有显著的增产、增收效果。该技术可大大提高化肥的增产效果和肥料利用率,有明显的集雨增墒效果,同时采用起垄覆膜种植马铃薯与垄沟种植谷子能够合理利用有限的工程集雨,有利于充分利用有限的降水资源,进行节约化农业经营。     

节水灌溉条件下冬小麦耗水规律及其生态基础研究

从土壤水分、作物生长发育及气象条件三个方面分析了冬小麦农田耗水变化特点。结果表明：在土壤水分状况较好条件下冬小麦农田耗水强度呈双峰曲线变化,不同灌溉处理的耗水高峰出现时期及其峰值不同,而与灌水时期一致,同时灌溉能够明显降低冬小麦利用土壤底墒水能力。在拔节以前冬小麦农田耗水与大气蒸发力呈显著直线相关;拔节后与其干物质积累以及土壤水分含量呈显著正相关,拔节期是冬小麦需水的生理生态临界期。     

农田土壤含水率与坚实度快速信息采集系统

介绍了一种农田土壤含水率与坚实度快速信息采集系统.本系统包括土壤介电传感器、圆锥指数传感器及深度传感器,可以快速、同步、实时地获得0～500mm范围内土壤剖面含水率与圆锥指数信息.同时,本系统还结合了GPS和GIS技术,实现了土壤参数的空间分析,可以更方便地把系统应用于农田信息管理.本系统为实现土壤水分和坚实度的同步测量搭建了一个智能化的试验平台,并且在与德国波恩大学农业工程研究所的合作中成功地应用于田间测量.     

潮州三百门电厂冷却水排放的数值模拟研究

海湾及潮汐河口的冷却水工程研究近年来受到人们的重视，由于受到潮汐的影响，其冷却水布置及热污染特性比河道及水库型更为复杂。采用数值模拟的方法，首先对电厂附近的潮流特性及冷却水输移扩散进行模拟计算，研究了电厂近海水域的水动力结构及其对冷却水排放的影响，给出电厂取水温升及热污染范围，为电厂取水设计工作提供依据。     

供水系统摇蚊污染特征的调查和分析

供水流程中的摇蚊污染影响水厂生产和自来水水质，S市水厂进行的摇蚊污染特征调查结果表明，污染水厂的摇蚊优势种是花翅摇蚊，水厂孳生的摇蚊来源于进厂原水，摇蚊主要孳生分布在水厂沉淀池。水厂沉淀池形成摇蚊污染的主要原因有：原水的悬浮物和丰富的藻类，沉淀池的温度、溶解氧、pH值，摇蚊幼虫对氯离子和混凝剂浓度的较强耐受性。