Nanofiber scaffolds provide numerous advantages over common carriers engineered for microorganisms. The most important advantage is an increased speed of primary surface colonization (up to four times faster), which shortens the time required for the areal biofilm formation and optimum performance of attached microorganisms (higher efficiency of biological activity of up to twice as fast). Image analysis predicts early formation of biofilm even in beginning stages; analysis of biofilm reveals the different structures of bacterial colonies on both scaffolds (higher porosity, size, and number of bacterial colonies on nanofiber's surface). The image analysis correlates well with determinations of dry matter (linear correlation of 0.96) and proteins (linear correlation of 0.89).
- MeSH
- biofilmy * MeSH
- kultivační média * MeSH
- nanovlákna * MeSH
- polyurethany MeSH
- poréznost MeSH
- Rhodococcus MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
Biomolecular and hydrochemical tools were used to evaluate natural attenuation of chlorinated ethenes in a Quaternary alluvial aquifer located close to a historical source of large-scale tetrachloroethylene (PCE) contamination. Distinct stratification of redox zones was observed, despite the aquifer's small thickness (2.8 m). The uppermost zone of the target aquifer was characterised by oxygen- and nitrate-reducing conditions, with mixed iron- to sulphate-reducing conditions dominant in the lower zone, along with indications of methanogenesis. Natural attenuation of PCE was strongly influenced by redox heterogeneity, while higher levels of PCE degradation coincided with iron- to sulphate reducing conditions. Next generation sequencing of the middle and/or lower zones identified anaerobic bacteria (Firmicutes, Chloroflexi, Actinobacteria and Bacteroidetes) associated with reductive dechlorination. The relative abundance of dechlorinators (Dehalococcoides mccartyi, Dehalobacter sp.) identified by real-time PCR in soil from the lower levels supports the hypothesis that there is a significant potential for reductive dechlorination of PCE. Local conditions were insufficiently reducing for rapid complete dechlorination of PCE to harmless ethene. For reliable assessment of natural attenuation, or when designing monitoring or remedial systems, vertical stratification of key biological and hydrochemical markers should be analysed as standard, even in shallow aquifers.
- MeSH
- biodegradace MeSH
- chemické látky znečišťující vodu analýza MeSH
- Chloroflexi MeSH
- ethyleny analýza MeSH
- halogenace MeSH
- monitorování životního prostředí * MeSH
- podzemní voda chemie MeSH
- tetrachlorethylen chemie MeSH
- vysoce účinné nukleotidové sekvenování MeSH
- železo analýza MeSH
- Publikační typ
- časopisecké články MeSH
Ion-exchange tap water demineralization for process water preparation results in a saline regeneration wastewater (20-100 mS cm(-1)) that is increasingly problematic in view of discharge. A coupled nanofiltration-membrane distillation (NF-MD) process is evaluated for the recovery of water and sodium chloride from this wastewater. NF-MD treatment of mixed regeneration wastewater is compared to NF-MD treatment of separate anion- and cation-regenerate fractions. NF on mixed regeneration wastewater results in a higher flux (30 L m(-2) h(-1) at 7 bar) compared to NF on the separate fractions (6-9 L m(-2) h(-1) at 30 bar). NF permeate recovery is strongly limited by scaling (50% for separate and 60% for mixed, respectively). Physical signs of scaling were found during MD treatment of the NF permeates but did not result in flux decline for mixed regeneration wastewater. Final salt composition is expected to qualify as a road de-icing salt. NF-MD is an economically viable alternative compared to external disposal of wastewater for larger-scale installations (1.4 versus 2.5 euro m(-3) produced demineralized water for a 10 m3 regenerate per day plant). The cost benefits of water re-use and salt recuperation are small when compared to total treatment costs for mixed regenerate wastewater.
- MeSH
- chlorid sodný chemie izolace a purifikace MeSH
- čištění vody přístrojové vybavení metody MeSH
- destilace přístrojové vybavení metody MeSH
- filtrace přístrojové vybavení metody MeSH
- membrány umělé MeSH
- odpadní produkty analýza MeSH
- odpadní voda chemie MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- práce podpořená grantem MeSH
The aim of this study was to evaluate the impact of short-term repeated exposure to a static magnetic field (induction 370 mT) on the Rhodococcus erythropolis cells. Specifically, it was ascertained the magnetic field's potential to influence degradation of a phenol substrate, cell growth and respiration activity (oxygen consumption) during substrate biodegradation. The experiment took place over 3 days, with R. erythropolis exposed to the magnetic field for the first day. During the experiment, different recirculation rates between the reactor and the magnetic contactor has been tested. Use of the magnetic field at higher recirculation rates (residence time in contactor was less than 7 min) stimulated substrate (phenol) oxidation by around 34%; which, in turn, promoted R. erythropolis growth by around 28% by shortening the lag- and exponential-phases and increasing bacterial respiration activity by around 10%.
- MeSH
- aerobióza MeSH
- biodegradace MeSH
- bioreaktory mikrobiologie MeSH
- fenol metabolismus MeSH
- magnetické pole * MeSH
- počítačová simulace MeSH
- Rhodococcus růst a vývoj metabolismus MeSH
- techniky vsádkové kultivace přístrojové vybavení MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- MeSH
- biodegradace * MeSH
- biofilmy růst a vývoj účinky záření MeSH
- biomasa * MeSH
- bioreaktory * mikrobiologie MeSH
- imobilizace MeSH
- mikrobiologie přístrojové vybavení trendy MeSH
- mikrobiota * MeSH
- nanovlákna * mikrobiologie MeSH
- odpadní vody * mikrobiologie MeSH
- počítače využití MeSH
- statistika jako téma MeSH
