声凝并联合雾化预处理及其在过滤除尘中的应用

根据声凝并理论和雾化湿式除尘理论,建立了燃煤飞灰在声场联合雾化加湿作为预处理的过滤式除尘实验装置。分别在声场、雾化加湿、声场与雾化加湿相结合3种预处理条件下进行实验,确定合适的加湿量范围,得出不同条件下燃煤飞灰的去除效果。在声场联合雾化加湿条件下,分别研究了声压级和雾化加湿量对飞灰的去除率的影响。结果表明,声场和雾化加湿联合作用能有效提高燃煤PM2.5去除率。以声场联合雾化加湿作为预处理进行过滤除尘实验,结果表明,虽然对高效滤料的除尘效率提高作用有限,但是该预处理可减轻滤袋负荷,有效延缓压差增长,降低清灰频率。由于采用表面覆膜滤材,加湿量控制得当可避免产生"糊袋"现象。     

不同好氧预处理方式对餐厨垃圾产甲烷的影响

为了研究不同好氧预处理方式对餐厨垃圾厌氧消化产甲烷的影响,通过建立3个模拟厌氧生物反应器,研究了传统厌氧生物反应器C1、上层好氧预处理-厌氧生物反应器C2和底部好氧预处理-厌氧生物反应器C3 3种不同操作条件下的产甲烷过程。结果表明,挥发性有机酸的累积使C1始终处于产甲烷滞后阶段;而C2、C3的好氧预处理通过加快易水解酸化组分和过量挥发性有机酸的好氧降解,有效缓解了酸性抑制,产甲烷滞后时间明显缩短至10 d内。第32天C2停止上层曝气后,在27 d内甲烷浓度达到了50%以上,同时,产甲烷速率迅速上升,并在第81天可达到峰值773 mL/(kg·d)。C3在第11天停止底部曝气后,虽然经过22 d的时间甲烷浓度即上升至50%,但之后产甲烷速率经历回落阶段后再次逐渐上升,在实验结束时仅达到517 mL/(kg·d)。上层曝气的好氧预处理方式所需曝气时间相对较长,但其产甲烷启动快,与底部曝气相比,其后期的甲烷化过程更稳定并可达到较高的产甲烷速率。     

响应面法优化黄粉虫幼虫处理餐厨垃圾饲养条件的研究

研究了黄粉虫幼虫处理餐厨垃圾的方法。首先在饲养温度、饲料含水量和饲养密度等条件下进行单因素实验,然后,以利用率为指标,运用响应面法优化了黄粉虫幼虫处理餐厨垃圾的饲养条件,结果表明,最佳饲养条件为饲养温度26.7℃、饲料含水量14.5%、饲养密度4.1头/cm2。在此饲养条件下,黄粉虫对餐厨垃圾利用率理论值为38.72%,实际餐厨垃圾利用率为38.88%,相对误差为0.41%,说明利用黄粉虫幼虫处理餐厨垃圾具有较好的效果。     

河流重金属污染底泥的稳定化实验研究

以实现河道疏浚底泥中富含的重金属Cu、Zn、Ni的稳定化为目标,选用EDTA、DTCR、Na2S、Na2S2O3、膨润土、水泥及自主研发的特殊胶凝材料作为稳定剂,对底泥中的重金属进行固化稳定,通过分析稳定后重金属浸出液浓度及赋存形态变化,探讨各药剂稳定效果,并寻求稳定剂的最佳投加量.研究表明,7种稳定剂对3种重金属的综合稳定化效果由好到差依次为:水泥> 胶凝材料> 膨润土> DTCR> 硫化钠> 硫代硫酸钠> EDTA;对Cu、Zn、Ni单种重金属而言,稳定效果最好的药剂分别为膨润土、胶凝材料及DTCR,而EDTA则使重金属浸出液浓度升高.除EDTA外,其他药剂对重金属Cu和Zn的稳定效果要明显优于Ni.根据稳定后重金属赋存形态变化结果,EDTA可使重金属可交换态比例升高,而膨润土对重金属4种形态分布基本无影响,其他药剂使重金属可交换态比例降低.     

Assessment of Aquifer Vulnerability in an Agricultural Area in Spain Using the DRASTIC Model

The assessment of aquifer vulnerability is a very important task, especially in agricultural areas because the quality and availability of groundwater affects both the sustainability of agriculture and the quality of life. In this study, an integrated approach is considered, with the use of the generic and agricultural DRASTIC models as well as a geographic information system (GIS), to assess groundwater vulnerability in the agricultural area of Barrax, in the province of Albacete, in Spain. Seven parameters—depth to water, net recharge, aquifer media, soil media, topography, impact of vadose zone media, and hydraulic conductivity of the aquifer (DRASTIC)—have been considered as weighted layers to enable an accurate groundwater risk mapping. The results of the generic DRASTIC model indicated very low vulnerability to contamination for Barrax groundwater due to limited urban and industrial development in the wider area. However, agricultural activities impose pressure to groundwater resources and the results of the agricultural DRASTIC model show that 6.86% of the study area is characterized by very high, 2.29% by high, 47.28% by medium, 38.28% by low, and the remaining 5.29% by no vulnerability to groundwater contamination. The distribution of nitrate concentration in groundwater in the area under study is quite well correlated with the agricultural DRASTIC vulnerability index. Sensitivity analysis was also performed to acknowledge statistical uncertainty in the estimation of each parameter used, to assess its impact, and thus to identify the most critical parameters that require further investigation. Depth to water and impact of vadose zone are the parameters that had the most noticeable impact on the generic DRASTIC vulnerability index followed by the soil media and topography. In contrast, the agricultural DRASTIC method is more sensitive to the removal of the depth to water parameter followed by the topography and the soil media parameters.     

真菌生物滤池净化苯乙烯废气的研究

采用接种Aspergillus candidus和Penicillium frequentans的真菌生物滤池处理苯乙烯废气,考察苯乙烯在生物滤池中的净化效果和物质转化特性。苯乙烯的进气质量浓度为200～800 mg/m3,气体流量分别为0.28,0.38和0.48 m3/h,对应的气体停留时间分别为60,45和35 s。试验结果表明:苯乙烯在真菌生物滤池中有较好的处理效果,最大去除能力达66.78 g/(m3.h),真菌生物滤池中二氧化碳的产生量和苯乙烯去除量呈线性关系。微生物分析结果表明,接种的Aspergillus candidus和Penicillium frequentans在反应器内能够长期保持优势地位。     

The Relation Between Sandstorms and Strong Winds in Xinjiang,China

With observational data spanning 1961–1999 from 90 meteorological stations in Xinjiang, China, the spatial and temporal characteristics of sandstorms and strong winds, and the contribution of strong winds to the occurrence of sandstormsare analyzed. Moreover, the dominant wind direction and minimumwind speeds during sandstorm periods are discussed. The research shows that although possessing similar climatic trends, sandstorms and strong winds in Xinjiang have opposite geographical distributions, i.e. places with more sandstorms show fewer strong winds. The contribution of strongwinds to sandstorms in northern Xinjiang is larger than that insouthern Xinjiang. The dominant wind directions clearly indicatethe paths of the weather systems that introduced the sandstorms.The minimum wind speeds in the sandstorms were over 10 ms^-1in northern and eastern Xinjiang and in the Turpan and Yanqi Basins of southern Xinjiang. In Tarim Basin of southern Xinjiang,however, the minimum wind speed was about 6–8 ms^-1, and even 6 ms^-1 at its southern edge.     

冀南野生药用资源植物研究

常用中药中以药用植物占多数，几乎凡具有特殊化学成分及生理作用的植物均可以作为药用植物利用。统计表明，冀南野生药用植物资源丰富，约170种。主要分布在西部山区。本文对其中部分重要药用资源植物的成分、功效作较详细介绍，其它只作一般性介绍：一、冀南重要野生药用植物