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821.
822.
选择两种常见的天然黏土矿物高岭石和蒙脱石,研究了有机污染物双酚A(BPA)在其表面的吸附及草酸对黏土矿物悬浮液中BPA光降解的影响.结果表明,BPA在两种黏土矿物表面的吸附量较小,吸附符合Langmuir等温式.在250W金属卤化物灯(λ≥360nm)照射下,草酸可显著促进BPA在高岭石和蒙脱石悬浮液中的光降解,降解动力学符合Langmuir-Hinshelwood方程. 降解速率受pH值的影响较大,pH=4.0时速度最快,光降解速率同时受草酸浓度的影响.最后,通过分析矿物中铁的化学环境及反应过程中铁浓度变化,分析了草酸促进BPA在黏土矿物悬浮液中光降解的可能机制. 相似文献
823.
The laccase-catalyzed conversion of bisphenol A (BPA) in aqueous solutions was studied in the absence and presence of nonionic
surfactant Triton X-100. It was found that the addition of Triton X-100 into the reaction system increased the conversion of BPA,
especially near the critical micelle concentration of Triton X-100. Also it was found that the stability of laccase was greatly improved
in the presence of TritonX-100. Studies on the endogenous fluorescence emission of laccase indicated that there existed an interaction
between Triton X-100 and laccase, which was beneficial to folding and stabilizating of laccase. The binding of Triton X-100 to the
laccase surface also mitigated the inactivation e ect caused by the free radicals and polymerization products. Under otherwise identical
conditions, a lower dosage of laccase was needed for the higher conversion of BPA in the presence of Triton X-100. 相似文献
824.
Microbial community structure in an integrated A/O reactor treating diluted
livestock wastewater during start-up period 总被引:1,自引:0,他引:1
In order to investigate the correlation between reactor performance and the microorganisms, an integrated A/O reactor was operated
for 72 days to treat diluted livestock wastewater. Chemical oxygen demand (COD) removal e ciency increased from 79% to 94%,
with total nitrogen (TN) removal e ciency from 37% to 50% (HRT 7.4 hr) when the influent COD and TN were ca. 1500 mg/L and 95
mg/L, respectively, and the outlet COD concentration was less than 100 mg/L at the end. Microbial community was monitored during
start-up period by denaturing gradient gel electrophoresis (DGGE) based on 16S rRNA gene. DGGE profiles showed that microbial
community had changed significantly during the start-up and these shifts were in accordance with the reactor performance. UPGMA
clustering analysis showed that 14 anaerobic samples fell into five main groups and so did the aerobic ones, but the grouping patterns
were di erent. Phylogenetic analysis indicated that microbial populations in the anaerobic compartment belonged to Firmicutes,
Proteobacteria, Chloroflexi and Bacteroidetes, while Proteobacteria, Bacteroidetes, Firmicutes, Verrucomicrobiae and Nitrospira were
present in the aerobic compartment. In the anaerobic compartment, more fermentative and acetogenic bacteria were detected during the
start-up while denitrifying bacteria faded away. Two functional populations such as Nitrospira defluvii and Dechloromonas denitrificans
were observed when nitrogen removal was high, indicating that simultaneous nitrification and denitrification occurred in the aerobic
compartment. 相似文献
825.
本文介绍了采用磁性载体与A/O联合工艺处理南京金陵石化研究院中试车间产生的含表面活性剂废水技术。采用磁性载体取代一般填料对MBBR工艺进行改良,磁性载体完成挂膜后,微生物的活性明显提高污水处理厂处理能力大幅提升。对比不同工艺处理相同污水时,改良MBBR工艺能保证污水能够平稳达标排放,同时提高了污水处理效率,降低了污水处理厂运行成本,提高了污水处理能力。 相似文献
826.
827.
828.
MBR与A/O工艺处理低温高盐废水的对比试验研究 总被引:1,自引:0,他引:1
就MBR和A/O工艺对高盐废水(50%海水)进行处理效果试验研究,比较了氨氮及总氮去除率随温度的变化情况。试验结果表明:低温条件下MBR与A/O工艺经过长期驯化能够稳定运行且获得较高的去除率;随温度从25qC降低到15℃、9℃、5℃时,MBR工艺的COD去除率从81.6%变化到79%、81.1%、82.7%,A/O工艺的COD去除率从67.9%变化到66.6%、65.5%、78.4%。MBR工艺的氨氮去除率从75%变化到68.3%、57.8%、54.6%,A/O工艺的氨氮去除率从70.4%变化到55.9%、49.2%、48.9%,可见COD受温度变化的影响要比氨氮受温度变化的影响小,但经过一段时间的驯化之后,去除效果逐渐变好,并且MBR工艺比A/O工艺受温度变化的冲击要小,处理效果也相对较好。 相似文献
829.
P.H.T. Schimit 《Ecological modelling》2010,221(9):1329-1655
There are several ways of controlling the propagation of a contagious disease. For instance, to reduce the spreading of an airborne infection, individuals can be encouraged to remain in their homes and/or to wear face masks outside their domiciles. However, when a limited amount of masks is available, who should use them: the susceptible subjects, the infective persons or both populations? Here we employ susceptible-infective-recovered (SIR) models described in terms of ordinary differential equations and probabilistic cellular automata in order to investigate how the deletion of links in the random complex network representing the social contacts among individuals affects the dynamics of a contagious disease. The inspiration for this study comes from recent discussions about the impact of measures usually recommended by health public organizations for preventing the propagation of the swine influenza A (H1N1) virus. Our answer to this question can be valid for other eco-epidemiological systems. 相似文献
830.