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951.
水解酸化-外循环(EC)厌氧-接触氧化工艺处理啤酒废水   总被引:1,自引:0,他引:1  
内蒙古自治区某啤酒厂采用水解酸化-外循环(EC)厌氧-接触氧化工艺处理啤酒废水。经过4个月的调试达到满负荷运行,系统稳定可靠,出水水质远优于GB19821-2005《啤酒工业污染物排放标准》。COD、BOD5、NH3-N、TN和TOC的去除率分别达97.5%、98.5%、85%、75%和98.5%。  相似文献   
952.
Photosynthetically active radiation (PAR) energy reaching on the vegetated surface is a key determinant of plant physiological processes. Most of biosphere or crop models use the ratio of PAR to incoming solar radiation (Rs), PAR/Rs, to convert Rs into PAR in order to reduce weather data-input requirements. Several existing models simply specify a constant ratio, PAR/Rs = 0.5. However, some field experiments have reported that the ratio PAR/Rs may not be constant. Previous empirical equations of PAR/Rs were derived based on the data of monthly or daily timescales collected from only a few measurement sites, hence they may not be appropriate to be used in current global biosphere models usually with hourly simulation time steps. Here, we represent the exponential correlation between PAR/Rs and sky clearness index (0-1) using hourly data from 54 Ameriflux measurement sites. It is found that PAR/Rs increases up to 0.6 in cloudy conditions when the clearness index (CI) is below ∼0.2, whereas it is nearly constant at ∼0.42 when CI is above 0.2. When the identified empirical equation is used in the model simulation, it results in −4 to 2% difference in the stomatal conductance compared to that using the constant ratio PAR/Rs = 0.5.  相似文献   
953.
Analytical solution for katabatic flow induced by an isolated cold strip   总被引:1,自引:0,他引:1  
An analytical model for katabatic flow induced by cold strip of finite width in the cross-slope direction but of infinite extent in the downslope direction is presented. The fluid is assumed to have a constant (eddy) viscosity, and the Coriolis force is neglected. A numerical simulation has been used to verify the model, which is shown to revert to the classical Prandtl model if the strip width goes to infinity. The effects of the strip width and slope angle on the katabatic flow are studied. The buoyancy and downslope velocity reach maximum values at the centre of the strip, and spread outwards in the cross-slope direction. The downslope wind maximum weakens for narrow strips and shallow slopes. In contrast to the Prandtl solution, which shows a counter flow above the wind maximum, our model predicts the counter flow to occur outside the strip. The cross-slope variation in the surface forcing induces cross-slope and slope-normal velocities, which are manifested in vortices at the strip edges. Below the wind maximum, the fluid above the cooling surface descends and moves toward the strip edge where it is detrained from the strip region. Replenishment of fluid into the strip region takes place above the wind maximum.  相似文献   
954.
零价铁还原降解活性染料   总被引:17,自引:0,他引:17  
曹加胜  王连生 《环境化学》1999,18(2):152-156
在分别通氮气,不通氮气和曝气的情况下,在水溶液中用零价铁还原降解活性染料。实验发现:在不同的氛围中,活性染料的降解程度不同,其降解程度为:暴气〉不通氮气〉通氮气。在不同通氮 和曝气的条件下,活性染料的降解过程中有黄色絮状沉淀生成,经红外光谱鉴定为三聚氯氰的取代产物。  相似文献   
955.
本文通过对江西省吉水县坡地资源现状、特点的分析,从未利用坡地、利用不充分坡地、利用不合理坡地3方面对吉水县坡地资源进行了潜力分析,并提出了开发利用坡地资源的途径  相似文献   
956.
ABSTRACT: One hundred and sixty-two rainfall-induced soil erosion tests were conducted to assist in predicting soil loss and subsequent increase in total suspended solids leaving a highway construction site during a rainfall event. A rainfall simulator and a water flume were constructed for the tests. Soil shear strength, compressive strength, rainfall intensity, and soil bed slope were treated as variables during the experiments. The soil with a higher shear strength resisted soil erosion better than lower strength soils. Soil loss was nearly independent of shear strength at low rainfall intensity but at high intensities, the shear strength was more important in resisting soil loss. Lower soil loss can be expected for cohesive soils if the compressive strength is high.  相似文献   
957.
Environmental Chemistry Letters -  相似文献   
958.
交联阳离子淀粉螯合剂对铬渣的处理研究   总被引:1,自引:0,他引:1  
合成了作为重金属螯合剂的交联阳离子淀粉 ,并将它用于铬渣的固化实验 ,对固化体的浸出毒性、表面浸出率、抗压强度等指标进行了测试。结果表明 ,添加高分子螯合剂后的固化体的浸出毒性降低 6 6 4 % ,远远小于国家标准的1 5mg/L ;2 8d后的表面浸出率仅为 1 0 -6数量级 ;抗压强度有所下降 ,但 2 8d养护后的抗压强度大于 30MPa ,符合填埋或建筑综合利用的强度要求  相似文献   
959.
Advanced reburning (AR) is effective for nitrogen oxides (NOx) reduction, which integrates the basic reburning (BR) with the injection of nitrogen agents and additive compounds. The basic reburning of poplar, cornstalk, wheat-straw and peanut shell, is studied on a boiler simulator facility (BSF). The influence of operating parameters and the synergistic effect of the injection of ammonia, urea or/and sodium carbonate on NOx reduction are investigated. The results show that an efficiency of 54–67% NOx reduction could be achieved during the basic reburning process under the optimum operating conditions and the efficiency would be increased if nitrogen agent is injected with the over-fire air or into the burnout zone. Further, co-injection of sodium carbonate with the nitrogen agent could make the NOx reduction process more thorough. On the whole, 85–92% NOx reduction could be achieved during the advanced reburning process with a reburning fuel heat input of 15–20%.  相似文献   
960.
本文首先概论了纤维(织物)阻燃技术,其次重点讨论了两种含磷本质阻燃PA纤维,一种是由含磷羟基羧酸或含磷二元羧酸与己二胺及己二酸共缩聚而后纺丝制得.另一种是用螺环磷酰氯与PA66及PA6纤维反应制得,后者具膨胀性。最后是综述了纤维(织物)阻燃技术的最新进展,包括新型表面改性技术及纳米技术等。  相似文献   
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