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71.
同步污水处理/发电技术-微生物燃料电池的研究进展 总被引:2,自引:0,他引:2
同步污水处理/发电技术的微生物燃料电池是利用生物催化剂直接把化学能转化为电能,具有能量转化率高、污泥产率低、反应条件温和等优点。本文阐述了微生物燃料电池的工作原理,反应器的类型及结构,综述了其最新的研究进展,并对微生物燃料电池在污水处理领域的发展方向作了展望。 相似文献
72.
微生物聚酯的合成和应用研究进展 总被引:11,自引:1,他引:11
微生物聚酯是由发酵技术生产、具有生物降解性的热塑性高分子材料。本文介绍了3-羟基丁酯均聚物(PHB)和共聚物的基本结构、生物降解性能、生物合成及其应用研究的进展。 相似文献
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Dennis J. O’Brien Gerard E. Senske 《Journal of the American Oil Chemists' Society》1994,71(9):947-950
Utilization of lipids containing eicosapentaenoic acid (EPA) produced by microorganisms requires processes for their efficient
recovery from microbial cells. Recovery of EPA from mycelia of the fungusPythium irregulare by solvent extraction with hexane-isopropanol (HIP) in a pilot-plant colloid mill was investigated. Extraction efficiencies
of 96% for lipid and EPA were achieved with a 3∶2 (vol/vol) HIP mixture by milling wet, filtered mycelia for 5 min at a solvent/dry
solids ratio of 100 L/kg. The process yielded a crude extract that contained up to 96% lipid and an EPA content as high as
24% (with no selectivity for EPA). 相似文献
75.
Vanesa Losada Jorge Barros‐Velzquez Jos M. Gallardo Santiago P. Aubourg 《European Journal of Lipid Science and Technology》2004,106(12):844-850
Slurry ice is a biphasic system consisting of small spherical ice crystals surrounded by seawater at subzero temperature. Its effect on lipid damage (hydrolysis and oxidation) was evaluated during the chilled storage of a fatty fish species, sardine (Sardina pilchardus). Slurry ice treatment was checked alone and in combination with ozone and compared to traditional flake icing during a 22‐day storage. Different lipid damage indices (free fatty acids, FFA; peroxide value, PV; thiobarbituric acid index, TBA‐i; fluorescent compounds, FR) were checked and compared to sensory assessment and nucleotide degradation (K value). According to lipid hydrolysis (FFA) and oxidation (PV and FR) developments, slurry ice showed an inhibitory effect (p <0.05) on lipid damage during storage, as well as an inhibition of nucleotide autolytic degradation. Ozonised slurry ice did not provide differences (p >0.05) from slurry ice alone when considering lipid hydrolysis, nucleotide degradation and some lipid oxidation indices (PV and FR), although a higher (p <0.05) TBA‐i was observed at day 22 of storage when compared to flake ice and slurry ice treatments. However, a lower (p <0.05) fluorescence development was observed for fish treated under ozonised slurry ice when compared to traditionally iced fish. Sensory assessment showed a higher shelf life for fish samples treated under ozonised slurry ice than for their counterparts under slurry ice (15 d versus 12 d), while flake icing led to a far shorter shelf life (5 d). According to sensory and biochemical (lipid matter and nucleotide) analysis, slurry ice has proved to be a promising technology for damage inhibition and quality retention in a fatty fish species such as sardine. Ozonised slurry ice was also shown to be useful, since a longer shelf life was obtained in the present experiment and a pro‐oxidant effect of ozone on sardine lipids was not proved. 相似文献
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采集城市内河水样,分别采用曝气增氧、碳源添加、生物投菌和综合修复等技术,在实验室进行水质修复模拟实验,并以水质参数、微生物多样性及丰度为鉴定指标,分析不同修复技术对城市河流水质的修复效果及其对河流微生物群落结构的影响。结果表明,曝气、生物投菌和综合修复技术可以提高河流微生物群落结构多样性,水体微生物群落以变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)、放线菌门(Actinobacteria)和疣微菌门(Verrucomicrobia)为主;而使用碳源添加技术的水样,河流微生物的多样性下降明显,变形菌门(Proteobacteria)的相对丰度达到了93%;水质修复方面,曝气增氧技术和生物投菌技术都仅能降低水体COD质量浓度,无法降低水体TN及NH+4-N质量浓度;碳源添加和综合修复技术,对水体TN和NH+4-N的去除效果明显,但投加碳源的河流水体中的COD质量浓度显著上升;相关性分析结果表明,影响水体微生物群落结构的主要环境因子为COD和DO。 相似文献
79.
Michael D. Dahlberg Richard L. Rohrer Daniel J. Fauth Richard Sprecher Gregory J. Olson 《Fuel》1993,72(12):1645-1649
A bacterium identified as Arthrobacter sp. was grown on dibenzothiophene (DBT) sulfone as a sole source of sulfur, producing sulfite and sulfate. Sulfur in DBT sulfone (1.0 mM) was nearly quantitatively converted to sulfate by the organism. The organism could also use DBT sulfone as a sole source of carbon and energy. There was evidence for transient accumulation of benzoic acid in the culture medium after growth of the cells slowed. The DBT sulfoxide analogue 9-fluorenone was converted by resting cells to a product identified as 1,10-dihydroxy-1,10-dihydrofluoren-9-one, suggesting that DBT sulfone may be metabolized via an angular hydroxylation resulting in carbon- sulfur bond cleavage. This strain of Arthrobacter showed no ability to desulfurize oxidized Illinois No. 6 coal. 相似文献
80.