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921.
Four materials, sodium carboxymethylcellulose (Na-CMC), sodium alginate (SA), polyvinyl alcohol (PVA), and chitosan (CTS), were prepared as supports for entrapping fungus Aspergillus fumigatus. The adsorption of synthetic dyes. Reactive Brilliant Blue KN-R, and Reactive Brilliant Red K-2BP, by these immobilized gel beads and plain gel beads was evaluated. The adsorption efficiencies of Reactive Brilliant Red K-2BP and Reactive Brilliant Blue KN-R by CTS immobilized beads were 89.1% and 93.5% in 12 h, respectively. The adsorption efficiency by Na-CMC immobilized beads was slightly lower than that of mycelial pellets. But the dye culture mediums were almost completely decolorized in 48 h using the above-mentioned two immobilized beads (exceeding 95%). The adsorption efficiency by SA immobilized beads exceeded 92% in 48 h. PVA-SA immobilized beads showed the lowest adsorption efficiency, which was 79.8% for Reactive Brilliant Red K-2BP and 92.5% for Reactive Brilliant Blue KN-R in 48 h. Comparing the adsorption efficiency by plain gel beads, Na-CMC plain gel beads ranked next to CTS ones. SA and PVA-SA plain gel beads hardly had the ability of adsorbing dyes. Subsequently, the growth of mycelia in Na-CMC and SA immobilized beads were evaluated. The biomass increased continuously in 72 h. The adsorption capacity of Reactive Brilliant Red K-2BP and Reactive Brilliant Blue KN-R by Na-CMC immobilized beads was 78.0 and 86.7 mg/g, respectively. The SEM micrographs show that the surface structure of Na-CMC immobilized bead is loose and finely porous, which facilitates diffusion of the dyes. 相似文献
922.
潜流式人工湿地污水处理系统硝化能力研究 总被引:43,自引:8,他引:43
研究了潜流式人工湿地内部不同填料层和沿水流方向硝化能力的变化.结果表明:潜流式人工湿地中,硝化能力沿水流方向逐渐减小.底部填料层,即炉渣层的氨氧化速率常数和亚硝酸氧化速率常数分别为1.99~6.89mg·(h·kg)-1和1.44~5.22mg(h·kg)-1,而床体上部土壤层的氨氧化速率常数和亚硝酸氧化速率常数分别为0.53~0.89mg·(h·kg)-1和0.96~1.39mg·(h·kg)-1.因此炉渣层的硝化能力要明显高于土壤层,底部炉渣层在硝化过程中起主要作用. 相似文献
923.
924.
925.
Aluminum salt coagulants were used prevalently in various water works.In this article,the effects of filtration on residual aluminum concentration and species distribution were researched by determining the concentration of diiferent aluminum species before and after single layer filter,double layer filter,and membrane filtration units.In the research,size exclusion chromatography(SEC)was used to separate colloidal and soluble aluminum,ion exchange chromatography(IEC)was used to separate organic and inorganic aluminum, and inductivity coupled plasma-atomic emission spectrometry(ICP-AES)was used to determine the aluminum concentration.The results showed that the rapid filtration process had the ability of removing residual aluminum from coagulant effluent water,and that double layer filtration was more effective in residual aluminum removal than single layer filtration,while nano filtration was more effective than micro filtration.It was found that when the residual aluminum concentration was below 1mg/L in sediment effluent,the residual aluminum concentration in treated water was above 0.2 mg/L.The direct rapid filtration process mainly removed the suspended aluminum.The removal of soluble and colloidal aluminum was always less than 10% and the natural small particles that adsorbed the amount of soluble or small particles aluminum on their surface were difficult to be removed in this process.Micro filtration and nano filtration were good technologies for removing aluminum;the residual aluminum concentration in the effluent was less than 0.05 mg/L. 相似文献
926.
PHBV泡沫吸油材料的制备及吸油性能研究 总被引:3,自引:0,他引:3
以PHBV为基材 ,在不同的助剂条件下采用真空冷冻干燥制备了几种PHBV泡沫吸油材料 ,并进行了吸油性能的比较。实验结果表明 :以三氯甲烷和乙基纤维素为助剂制备的PHBV泡沫吸油材料的吸油率、二次吸油率随着助剂量的增加而有所提高 ,而以乙酸纤维素为助剂制备的PHBV泡沫吸油材料的吸油率、二次吸油率随着助剂量的增加而有所降低 ,三者保油率的变化不明显。当达到最佳配比时 ,三种助剂制备的PHBV泡沫在 2 6℃原油下的吸油率可达 2 0倍 ,在 17℃原油下的吸油率可达 30倍。从吸油性能、成本和环保等方面综合考虑 ,以乙酸纤维素作为助剂的制备方法为最佳 相似文献
927.
吸附胶束絮凝(AMF)法可用于去除水体中的各种污染物,为了对其处理过程中的行为加以控制,以阴离子表面活性剂SDS和铝盐为模型,通过Zeta电位、表面张力和平均粒度等分析方法,研究了吸附胶束絮凝法对苯酚、苯胺的分离去除及苯酚、苯胺对其吸附胶束絮凝过程的影响。结果表明:苯酚的存在没有对表面活性剂胶束的絮凝产生明显的影响,由于Al3+的存在,推测苯酚以络合物的形式吸附在胶束的斯特恩层,并可通过铝盐对胶束的絮凝而与水相分离去除,其去除率在40%~50%左右。而极少量的极性有机物苯胺可使表面活性剂胶束的絮凝发生较大改变,推测苯胺的存在抑制了絮凝胶团的形成。当苯胺浓度低于100 mg/L时,苯胺的去除率可达90%左右。该研究为胶束絮凝分离溶解性有机物提供了实验参考。 相似文献
928.
关于新疆环境应急能力建设的探讨 总被引:3,自引:0,他引:3
阐述了新疆环境应急能力建设的重要性,对新疆环境应急现状中存在的问题进行了分析,提出了加强环境应急能力建设的几点建议。 相似文献
929.
Increasing attention has been paid to phosphate-accumulating organisms(PAOs)for their important role in biological phosphorus removal.In this study,microbial communities of PAOs cultivated under different carbon sources(sewage,glucose,and sodium acetate) were investigated and compared through culture-dependent and culture-independent methods,respectively.The results obtained using denaturing gradient gel electrophoresis(DGGE)of polymerase chain reaction-amplified 16S rDNA fragments revealed that the diversity of bacteria in a sewage-fed reactor(1#)was much higher than in a glucose-fed one(2#)and a sodium acetate-fed one(3#);there were common PAOs in three reactors fed by different carbon sources.Five strains were separated from three systems by using a phosphate- rich medium;they were from common bacteria isolated and three isolates could not be found in DGGE profile at all.Two isolates had good phosphorus removal ability.When the microbial diversity was studied,the molecular biological method was better than the culture-dependent one.When phosphorus removal characteristics were investigated,culture-dependent approach was more effective. Thus a combination of two methods is necessary to have a comprehensive view of PAOs. 相似文献
930.
森林凋落物对土壤酸化缓冲作用的初步研究 总被引:6,自引:0,他引:6
阔叶树木荷凋落物的灰分元素含量以及分解速率大大高于针叶树杉木凋落物。相比之下,木荷凋落物具有较高的缓冲酸化的潜在能力。覆盖木荷凋落物的土壤,其下渗液盐基含量和PH值与对照相比显著较高,而土壤本身的盐基饱和度和有机质含量也显著较高,土壤酸度和Al/Ca显著较低,即太荷凋落物对土壤酸化有较高的缓冲能力,而杉木凋落物则不然。 相似文献