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Biodegradation of 2-methylisoborneol by bacteria enriched from biological activated carbon 总被引:1,自引:1,他引:0
Rongfang YUAN Beihai ZHOU Chunhong SHI Liying YU Chunlei ZHANG Junnong GU 《Frontiers of Environmental Science & Engineering》2012,6(5):701-710
One of the most common taste and odour compounds (TOCs) in drinking water is 2-methylisoborneol (2-MIB) which cannot be readily removed by conventional water treatments. Four bacterial strains for degrading 2-MIB were isolated from the surface of a biological activated carbon filter, and were characterized as Micrococcus spp., Flavobacterium spp., Brevibacterium spp. and Pseudomonas spp. based on 16S rRNA analysis. The removal efficiencies of 2-MIB with initial concentrations of 515 ng·L-1 were 98.4%, 96.3%, 95.0%, and 92.8% for Micrococcus spp., Flavobacterium spp., Brevibacterium spp. and Pseudomonas spp., respectively. These removal efficiencies were slightly higher than those with initial concentration at 4.2 mg·L-1 (86.1%, 84.4%, 86.7% and 86.0%, respectively). The kinetic model showed that biodegradation of 2-MIB at an initial dose of 4.2 mg·L-1 was a pseudo-first-order reaction, with rate constants of 0.287, 0.277, 0.281, and 0.294 d-1, respectively. These degraders decomposed 2-MIB to form 2-methylenebornane and 2-methyl-2-bornane as the products. 相似文献
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Mehdi Adjeroud Aurélie Guérécheau Jeremie Vidal-Dupiol Jean-François Flot Sophie Arnaud-Haond François Bonhomme 《Marine Biology》2014,161(3):531-541
Clonality and genetic structure of the coral Pocillopora damicornis sensu lato were assessed using five microsatellites in 12 populations from four islands of the Society Archipelago (French Polynesia) sampled in June 2008. The 427 analysed specimens fell into 132 multilocus genotypes (MLGs), suggesting that asexual reproduction plays an important role in the maintenance of these populations. A haploweb analysis of ITS2 sequences of each MLG was consistent with all of them being conspecific. Genetic differentiation was detected both between and within islands, but when a single sample per MLG was included in the analyses, the populations turned out to be nearly panmictic. These observations provide further evidence of the marked variability in reproductive strategies and genetic structure of P. damicornis throughout its geographic range; comparison with results previously obtained for the congeneric species Pocillopora meandrina underlines the importance of life history traits in shaping the genetic structure of coral populations. 相似文献
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Biofuels are sustainable fuels produced from modern biomass such as plants and algae. Biodiesel has high lubricity and ultra-low sulfur content. Biodiesel is produced from vegetable oil by transesterification. Actually, practical biodiesel production is limited by the low reaction rate of transesterification of vegetable oil with methanol catalyzed by CaO. Here we designed an efficient catalyst: benzyl bromide-modified CaO. Using benzyl bromide-modified CaO, we obtained a 99.2 % yield of fatty acid methyl esters in 3 h, compared with 35.3 % yield using commercial CaO under the same reaction conditions. The improved catalytic activity is explained by better fat diffusion to the surface of the benzyl bromide-modified CaO. The novelty of our findings is the much higher yield of our method compared to literature data on heterogeneous catalysis. In addition, the lifetime of our catalyst is excellent. 相似文献
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汽车门禁系统已成为汽车智能与安全领域的重要一部分.车主手持智能钥匙靠近汽车,通过车载基站与钥匙的双频通信,实现车门的开与关,还可实现发动机的一键启动.同时,对信号加密采用了改进的AES算法,加入了循环扩展密钥,加大了密码的破解难度.并对整个系统进行了建模仿真,分析了信号传输的误码率.图6,表1,参5. 相似文献
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