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201.
膜法处理含油废水研究进展   总被引:7,自引:0,他引:7  
本文简要概述了微滤、超滤和反渗透等膜法处理含油废水的研究进展。  相似文献   
202.
Nine selected elements (Cu, Pb, As, Zn, Co, Ni, Cr, Cd and Fe) were determined by inductively coupled plasma atomic emission spectroscopy in 15 samples from the tailings pond (Zelazny Most) and waste water streams (Moskorzynke and Rudna) in the Kupferschiefer mining district in Southwest Poland. Waste water from mining and industry enter the Zelazny Most pond. The water then flows through Moskorzynke and Rudna streams, and discharges into the River Odra. The analytic results indicate that the contamination with Cu, Pb, Zn, As, Co, Cd and Fe extend about 6km along the streams in contrast to the nonpolluted samples close the River Odra. Their concentrations reach a level, which could be toxic for plants, animals and humans. The contamination with Ni and Cr continued at least 20km along Rudna stream. Besides mechanical transport, redox conditions and Corg contents also played an important role for trace element and Fe contamination in Rudna stream. The samples with high Corg contents have also high contents of trace metals. In Moskorzynke stream the element contamination was mainly caused by mechanical transport of particles. Polyaromatic hydrocarbon (PAH), which is abundant in Kupferschiefer, is toxic for animals and humans. The PAH concentration in the stream sediments was determined by GC and GC/MS. The results indicate that the contamination of PAH reaches 6 and 17mgkg–1 in samples TP1 and RS6, respectively. In the other samples, the PAH contents are lower than 3mgkg–1. Some PAH could be solved by waste water in the tailings pond and migrated to the stream sediments. Some PAH might be contained in particles which were transported mechanically from the tailings pond into stream sediments.  相似文献   
203.
本文利用地震非均匀度方法对汶川8.0级地震开展了震例研究,较系统地分析了汶川地震前地震非均匀度的时空演化特征。研究结果表明,汶川地震前在震中及附近地区存在明显的地震非均匀度中短期异常,2001年2月23日雅江6.3级地震可能是汶川地震前的首发地震,具有前震指示意义;根据近期GL值时空演化图像,探讨了我国西南地区的震情发展趋势。  相似文献   
204.
细胞融合高效菌株对氧乐果生产废水中有机磷的去除   总被引:1,自引:0,他引:1  
两株具有单重抗药性的突变菌株S-8菌株(Str+,Kan-)和K-17菌株(Str-,Kan+),其活性污泥对氧乐果生产废水有机磷的去除率分别达58%和51%,对COD的去除率分别达78%和82%。以S-8菌株和K-17菌株作为亲本菌株进行原生质体融合,其正交试验的优化条件为:PEG浓度40%;促融时间4min;用0.015 mol/LCa2+处理;pH 10.0;添加20μL/ml细胞壁再生引物,融合率达4.617×10-5。用双层药物平板筛选融合细胞,获取了既能降解有机磷又能降低COD值的融合子F2。结果表明,用融合子F2菌株增殖而成的活性污泥对上述氧乐果生产废水有机磷的去除率达78%,COD的去除率达88%。  相似文献   
205.
探讨了氧化石墨烯(GO)和碳纳米管(CNT)组成的二元杂化物在聚氨酯泡沫上的阻燃协效作用。利用层层自组装方法,将氧化石墨烯和碳纳米管构成的涂层构筑于软质聚氨酯泡沫的表面,然后通过宏观燃烧测试、锥形量热仪分析等手段对涂层改性的泡沫材料的阻燃性能进行分析。研究结果表明,相较于单一组分(CNT或GO),二元杂化物(CNT/GO)改性的聚氨酯泡沫材料显示出更低的热释放速率峰值和总的热释放量,并且其燃烧后残留的炭渣结构最为完整。因此,由GO与CNT组成的二元杂化物涂层具有更高的阻燃效果。  相似文献   
206.
Due to the influences of precursors emissions, meteorology, geography and other factors, ozone formation sensitivity (OFS) is generally spatially and temporally heterogeneous. This study characterized detailed spatial and temporal variations of OFS in Guangdong-Hong Kong-Macao Greater Bay Area (GBA) from 2012 to 2016 based on OMI satellite data, and analyzed the relationships of OFS with precursors emissions, meteorology and land use types (LUTs). From 2012 to 2016, the OFS tended to be NOx-limited in GBA, with the value of FNR (HCHO/NO2) increasing from 2.04 to 2.22. According to the total annual emission statistics of precursors, NOx emissions decreased by 33.1% and VOCs emissions increased by 35.2% from 2012 to 2016, directly resulting in OFS tending to be NOx-limited. The Grey Relation Analysis results show that total column water (TCW), surface net solar radiation (SSR), air temperature at 2 m (T2) and surface pressure (SP) are the top four meteorological factors with the greatest influences on OFS. There are significant positive correlations between FNR and T2, SSR, TCW, and significant negative correlations between FNR and SP. In GBA, the OFS tends to be NOx-limited regime in wet season (higher T2, SSR, TCW and lower SP) and VOCs-limited regime in dry season (lower T2, SSR, TCW and higher SP). The FNR displays obvious gradient variations on different LUTs, with the highest in “Rural areas”, second in “Suburban areas” and lowest in “Urban areas”.  相似文献   
207.
Ammonia(NH3) volatilization is one of the primary pathways of nitrogen(N) loss from soils after chemical fertilizer is applied, especially from the alkaline soils in Northern China, which results in lower efficiency for chemical fertilizers. Therefore, we conducted an incubation experiment using an alkaline soil from Tianjin(p H 8.37–8.43) to evaluate the suppression effect of Trichoderma viride(T. viride) biofertilizer on NH3 volatilization, and compared the differences in microbial community structure among all samples. The results showed that viable T. viride biofertilizer(T) decreased NH_3 volatilization by 42.21% compared with conventional fertilizer((CK), urea), while nonviable T. viride biofertilizer(TS) decreased NH_3 volatilization by 32.42%. NH_3 volatilization was significantly higher in CK and sweet potato starch wastewater(SPSW) treatments during the peak period. T. viride biofertilizer also improved the transfer of ammonium from soil to sweet sorghum. Plant dry weights increased 91.23% and 61.08% for T and TS, respectively, compared to CK. Moreover, T. viride biofertilizer enhanced nitrification by increasing the abundance of ammonium-oxidizing archaea(AOA) and ammonium-oxidizing bacteria(AOB). The results of high-throughput sequencing indicated that the microbial community structure and composition were significantly changed by the application of T. viride biofertilizer. This study demonstrated the immense potential of T. viride biofertilizer in reducing NH_3 volatilization from alkaline soil and simultaneously improving the utilization of fertilizer N by sweet sorghum.  相似文献   
208.
JAZ型絮凝剂对活性染料的絮凝效果   总被引:2,自引:0,他引:2  
本文介绍了新近开发的JAZ絮凝凝剂地水样中活性艳红K-2BP,活性紫H-2R和活性黑K-BR染料的絮凝效果及PH值和投药比对脱色率的影响。在中性和弱酸性中絮凝效果好。投药比增大脱色率增加。对活性艳红和活性紫,起始浓度增加则达到88.5%脱色率的投药比降低。对三种活性染料配水和活性 染料配水和活性黑染料生产水脱色率均可达到99%,处理液残余色度在20倍以下。  相似文献   
209.
盐泽螺旋藻对染料的吸附性能研究   总被引:13,自引:0,他引:13  
陈勇生  黄国兰 《环境化学》1998,17(5):439-443
本文研究了经过一定处理后失活的盐泽螺旋藻对七种染料的吸附行为;同时探讨了不同重金属对失活的盐泽螺旋藻吸附染料的影响。  相似文献   
210.
香蒲植物提取物的抑藻作用及其分离鉴定   总被引:22,自引:0,他引:22  
  树桂  赵凡 《环境化学》1997,16(3):268-271
对香蒲类植物的花粉蒲黄中的抑藻物质进行提取、分离、鉴定。分别用抑藻圈和半杀死剂量法研究其乙酸乙酯、丙酮、乙醚提取物的抑藻活性。并从乙酸乙酯提取物中分离出两种抑藻活性的物质。  相似文献   
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