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871.
膜覆盖条垛堆肥技术与应用案例 总被引:1,自引:0,他引:1
膜覆盖技术是一种改良的静态条垛堆肥技术,主工艺过程与传统高温好氧发酵工艺过程类似。介绍了膜覆盖堆肥系统的核心技术——功能性覆盖膜、曝气系统、卷膜设备;通过对膜覆盖系统的优势和不足的分析,得到该技术的适用范围;介绍了两个应用案例。 相似文献
872.
873.
SPMD技术的应用与研究进展 总被引:4,自引:1,他引:3
综述了半透膜装置(SPMD)在环境科学研究中的进展状况。回顾了SPMD的产生历程,分析了SPMD富集和监测疏水有机污染物的原理。综述了SPMD在气、水、沉积物、化肥及石油等环境中疏水性有机污染物的监测、污染物的生物有效性的评价、类脂物样品中污染物的提取、有机污染物的毒理作用的测定等几方面的研究进展状况。并就SPMD在上述几个方面研究、应用中的不足以及今后发展的方向提出了一些看法。 相似文献
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875.
N. A. Kuznetsova 《Russian Journal of Ecology》2003,34(4):248-254
Trends in the diversity of structural organization of soil animal communities are analyzed using an example of the taxocenes of springtails, small soil arthropods. Different methods for describing the structure of communities are considered. On the basis of parameters characterizing specialization and stability of communities, several patterns of their organization in springtails are distinguished. It is shown that the new approach offers new opportunities in forecasting community dynamics under the effects of natural and anthropogenic factors. 相似文献
876.
In an attempt to increase the range of analytical techniques able to monitor ultimate degradation stages of degradable, biodegradable, and bioresorbable polymers, capillary zone electrophoresis (CZE) was used to analyze tentatively oligomers formed during thermal condensation of lactic, glycolic, anddl-3-hydroxybutyric acids. The influence of the buffer and of capillary coating are discussed in terms of electroosmotic flow. Typical analyses were first performed using a 0.1M borate buffer (pH 8.9) with anodic injection. In the case of lactic acid, seven peaks were well separated, while only three peaks were observed for glycolic acid. A more complex situation was found fordl-3-hydroxybutyric acid oligomers. The first five peaks were split. The major component of each doublet was attributed to hydroxy-terminated oligomers, whereas the satellite peaks were assigned to oligomers bearing a C=C double bond at the noncarboxylic terminus. CZE of pH-sensitive lactic acid oligomers was also performed in 0.05M phosphate buffer (pH 6.8) with cathodic injection after physical coating of the fused-silica capillary with DEAE-Dextran. The buffer-soluble fraction present in lactic acid oligomers was extracted from a dichloromethane solution. Extracts issued from different batches of lactic acid condensates gave a constant water-solubility pattern whose cutoff was at the level of the decamer. CZE was also used to monitor thein vitro aging of aqueous solutions of these water-soluble oligomers. The lactyllactic acid dimer appeared more stable than higher oligomers, thus showing that ultimate stages of the degradation did not proceed at random. These physicochemical characteristics were used to complement the degradation pathway based on diffusion of oligomers duringin vitro aging of large size lactic acid plates made by compression molding. CZE data showed that lactic acid was the only component which was released in the aqueous medium during degradation.Presented by C.B. at the 4th International Workshop on Biodegradable Plastics and Polymers, October 11–14, 1995, Durham, NH, USA. 相似文献
877.
MBR处理抗生素废水实验研究 总被引:1,自引:0,他引:1
以沈阳某制药厂为例,以制药厂废水处理工程UASB出水为原水,开展了MBR处理抗生素废水小试实验,对CODcr去除效果、氨氮去除效果以及膜的清洗与再生进行了研究。研究表明:当进水CODcr负荷小于7kg/m·3d时,出水CODcr在40mg/L以下,出水氨氮在40mg/L以下,处理效果良好;采用5%NaOH以及0.5%NaClO溶液作为化学清洗药剂时,清洗效果较好。 相似文献
878.
介绍了在实验室中采用膜生物反应器与A/O法结合处理生活污水的运行情况,研究膜生物反应器脱氮效能,借以为后续的研究及应用提供参考。 相似文献
879.
880.