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801.
Maria Rutkowska Katarzyna Krasowska Aleksandra Heimowska Grażyna Adamus Michał Sobota Marta Musioł Henryk Janeczek Wanda Sikorska Andrej Krzan Ema Žagar Marek Kowalczuk 《Journal of Polymers and the Environment》2008,16(3):183-191
Degradation of atactic poly[(R,S)-3-hydroxybutyrate] (a-PHB) binary blends with natural poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV, 12 mol% of 3HV units), has been investigated and compared with plain PHBV in the compost containing
activated sludge and under marine exposure conditions in the dynamic water of the Baltic Sea. Characteristic parameters of
compost and the Baltic Sea water were monitored during the incubation period (6 weeks) and their influence on the degree of
biodegradation is discussed. After specified degradation times of the experiments the weight loss of the samples, surface
changes, changes in molecular weight and polydispersity as well as changes of the composition and thermo-mechanical properties
of the blends have been evaluated. Macroscopic observations of the samples were accompanied by investigations using optical
microscopy, size-exclusion chromatography (SEC), nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC)
and tensile testing. The degree of degradation of blends of a-PHB with PHBV depends on the blend composition and environmental
conditions. In both environments studied the weight loss of plain PHBV was more significant than changes the molecular weight.
In both environments only enzymatic degradation of the blends, which proceeds via surface erosion mechanisms, was observed
during the incubation period. 相似文献
802.
The peroxynitrite/porphyrin biomimetic system was established to investigate the effects of peroxynitrite on benzo[a]pyrene (B[a]P) metabolism. Through the comparison of three model systems consisting of different iron porphyrins, we found that the peroxynitrite/T(p-Cl)PPFeCl system showed the highest catalytic efficiency in the metabolism of B[a]P. We analyzed the B[a]P metabolites produced from this system by RP-HPLC method and firstly identified the formation of nitrobenzo[a]pyrenes which are the special metabolites of B[a]P induced by peroxynitrite. 相似文献
803.
Alga-lysing bacteria have been paid much attention to in recent years. In this study, the alga-lysing strain P05 which was isolated from an immobilizing biosystem was immobilized by coke and elastic filler, forming two biological reactors. The removal efficiencies of algae, NH3-N and organic matter using the two reactors were studied. The results showed that strain P05 was an ideal algal-lysing bacteria strain because it was easy to be immobilized by coke and elastic filler which are of cheap, low biodegradability and the simple immobilization procedure. After 7 d filming, the biological film could be formed and the reactors were used to treat the eutrophic water. These two reactors were of stability and high effect with low cost and easy operation. The optimal hydraulic retention time (HRT) of each reactor was 4 h. The algae removal rates were 80.38% and 82.1% (in term of Chl-a) of coke reactor and filler reactor, respectively. And that of NH3-N were 52.3% and 52.7%. The removal rates of CODMn were 39.03% and 39.64%. The strain P05 was identified as Bacillus sp. by PCR amplification of the 16S rRNA gene, BLAST analysis, and comparison with sequences in the GenBank nucleotide database. 相似文献
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实践教学是大学培养的重要环节,有利于培养学生的创新能力和应用能力,为培养符合社会发展需求的综合素质高的工科专业人才,基于"三重一高"的思想,构建工科专业"三位一体"的实践教学体系,包括基于系统化的基础实践教学、基于工程化的专业技能实训教学和基于综合化的专业素质培育教学三个方面,并将其思想应用于安全工程专业实践教学建设。 相似文献
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微生物水处理技术因运行成本低、处理量大、环境影响小等优点,被广泛的用于市政污水和工业废水的处理.微生物水处理的本质过程是生物催化氧化,涉及不同微生物种群间物质、能量和电子传输过程,而微生物胞外电子传递过程是影响其处理效率的关键因素之一.本研究立足于微生物氧化的原理,从介体材料强化、光电磁强化及微生物电化学强化等角度,系统论述了铁基材料、碳基材料、光、电、磁等对微生物电子传递过程的影响与机制.在此基础上,本论文总结了微生物电化学系统原理,分析了该系统中各类强化材料、强化技术对微生物胞外电子传递的影响,揭示了强化条件下污染物高效转化的作用机制,介绍了基于各种强化原理的系统构建因素及应用现状,并展望了该技术的发展趋势及存在的挑战. 相似文献
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810.