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81.
腐殖活性污泥生化特征及处理效能   总被引:2,自引:0,他引:2  
为探讨腐殖活性污泥的生物化学特征及其作用机理,对腐殖生物填料进行扫描电镜和能谱(SEM-EDAX)测定,表明填料中主要组成元素为C、O、Si,同时含有少量Al、S、Fe. 腐殖活性污泥与普通活性污泥中若干特征菌群的对比分析表明,腐殖活性污泥中的一般细菌总量、硝酸菌、亚硝酸菌、脱氮菌及放线菌含量明显高于普通活性污泥;腐殖活性污泥中有机质的质量分数比普通活性污泥低,但腐殖酸及富里酸和胡敏酸质量分数明显高于普通活性污泥;腐殖活性污泥法运行的SBR反应器对CODCr、TP和TN的去除效果优于普通SBR反应器,分别高出4%、14%和10%.  相似文献   
82.
The aim of this article is the study of the potential relationships between PAHs contamination, physicochemical parameters, and microbial activity in industrial soils. The research was based on two series of measurements. The first was conducted in June 2013 and the second in November 2013. Samples used in study were collected from the area of fuel handling and a loading station, located in the Silesia region of Poland. All collected samples were characterized by the following analytical procedures: PAHs content analysis, the basic physical and chemical parameters determinations (pH, CEC, humic acids content, TC, TN, TP) and microbial activity analysis. The obtained results were also subjected to statistical analysis, based on the Pearson's correlation coefficient calculations.

Results collected during described above procedure show that: the PAHs content was highly positively correlated with C and N contents (p < 0.001) and moderately correlated with humic acids and P contents (p < 0.01). This phenomenon confirms the thesis that the increase of soil organic matter content promotes accumulation of hydrophobic organic compounds such as PAHs. Microbiological analysis shows that bacteria from the mesophilic group are most resistant to PAHs contamination. This information indicates that the organisms belonging to this group should be considered as potentially useful in the soil bioremediation processes.  相似文献   

83.
李文英  李阳  马艳飞  张俊锋  李秋红  何芳 《化工进展》2020,39(10):4191-4199
为更好地回收含油污泥(即油泥)中可用资源,国内外油泥资源化处理方法不断更新和突破,并在室内实验研究阶段取得较好的处理效果。本文从油泥的高温热处理法、常温法、低温冻融法三个方面综述了热解、微波、萃取等油泥资源化处理方法的研究进展、优缺点以及适用条件等。热解法油品回收率达95.8%,具有油泥处置彻底、油品回收质量高的特点。电动力学法处理油泥,油泥减量化达44.3%,采用浮选法,油泥减量化达95%,两种方法均具有操作简单、易实施、适合大批量处理的特点,工程化应用潜力较大。油泥来源不同,性质各异,采用单一技术难以实现大量油泥的资源化和无害化目标。多项技术联合,如热解法联合浮选法或电动力学法处理大规模油泥能提高油品回收率和质量,降低残油率和处理成本,将成为油泥资源化处理技术的发展方向。  相似文献   
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85.
Non‐corrosive, carbon‐based materials are usually used as anodes in microbial fuel cells (MFCs). In some cases, however, metals have been used that can corrode (e.g. copper) or that are corrosion resistant (e.g. stainless steel, SS). Corrosion could increase current through galvanic (abiotic) current production or by increasing exposed surface area, or decrease current due to generation of toxic products from corrosion. In order to directly examine the effects of using corrodible metal anodes, MFCs with Cu were compared with reactors using SS and carbon cloth anodes. MFCs with Cu anodes initially showed high current generation similar to abiotic controls, but subsequently they produced little power (2 mW m‐2). Higher power was produced with microbes using SS (12 mW m‐2) or carbon cloth (880 mW m‐2) anodes, with no power generated by abiotic controls. These results demonstrate that copper is an unsuitable anode material, due to corrosion and likely copper toxicity to microorganisms. © 2013 Society of Chemical Industry  相似文献   
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88.
Chemokines are a burgeoning family of chemotactic cytokines displaying a broad array of functions such as regulation of homeostatic leukocyte traffic and development, as well as activating the innate immune system. Their role in controlling early and late inflammatory stages is now well recognized. An improper balance either in chemokine synthesis or chemokine receptor expression contributes to various pathological disorders making chemokines and their receptors a useful therapeutic target. Research in this area is progressing rapidly, and development of novel agents based on chemokine/chemokine receptors antagonist functions are emerging as attractive alternative drugs. Some of these novel agents include generation of chemokine-derived peptides (CDP) with potential agonist and antagonist effects on inflammation, cancer and against bacterial infections. CDP have been generated mainly from N- and C-terminus chemokine sequences with subsequent modifications such as truncations or elongations. In this review, we present a glimpse of the different pharmacological actions reported for CDP and our current understanding regarding the potential use of CDP alone or as part of the novel therapies proposed in the treatment of microbial infections and cancer.  相似文献   
89.
The effect of a decrease in operating temperature on the performance of two 10 dm3 anaerobic baffled reactors (ABR) was examined in terms of steady state chemical oxygen demand (COD) removal efficiency. To minimise variations, and have a totally biodegradable feed, a synthetic carbohydrate (sucrose)–protein (meat extract) substrate was used. The reactors were operated at 20 h hydraulic retention time (HRT), 4 g dm−3 COD, and 35°C as a base-line condition. Because of their different histories, the reactors responded differently to a decrease in operating temperature to 25°C. Reactor 1 remained stable at 97% COD removal, whereas Reactor 2 decreased to 93% removal, but rose to 97% after adding an effluent recycle of 0·25. At 15°C, the efficiency of Reactor 1 dropped to 75%, while the removal of Reactor 2 declined to 83%, and no improvement in efficiency occurred with an effluent recycle at 0·25. At 25°C, the decreased rate of catabolism of the slow-growing syntrophs and methanogens resulted in a shift of the volatile fatty acids (VFA) peak to the second compartment. However, the biomass present in the reactor prevented VFAs breaking through in the effluent. Nevertheless, at 15°C VFAs were present in the effluent, perhaps due to the lower rates of metabolism and an increase in the Ks for VFAs. Finally, at 15°C part of the increase in the effluent COD was due to the enhanced production of soluble microbial products (SMP), or a decrease in their metabolism, with these compounds constituting some 10% of the inlet COD. © 1997 SCI.  相似文献   
90.
MFC聚苯胺碳纳米管阳极电化学法制备及其性能   总被引:2,自引:4,他引:2  
引言经济的高速可持续发展,迫切需要新能源和可再生能源的研究和开发。而微生物燃料电池(MFC)是利用电化学方法将微生物代谢能转化为电能的一种新型能源技术[1]。虽然MFC功率密度和输出电压近年来有了很大提高,但和普通氢燃料电池相比,MFC的库仑效率和输出功率都较低,实现MFC技术的商业化应用还需要多方面技术研  相似文献   
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