93 research outputs found
Novel low-fouling membrane bioreactor (MBR) for industrial wastewater treatment
A novel antifouling coating of ultrafiltration (UF) commercial membranes, based on a polymerisable bicontinuous microemulsion (PBM) technique, was developed and tested for the first time in a membrane bioreactor (MBR) using an artificial model textile dye wastewater and compared with a commercial uncoated UF membrane. The results showed that the commercial MBR module faced severe fouling problems whereas the novel coated PBM MBR module reduced the fouling significantly. The analysis of fouling rate using a resistance model confirms that PBM coated membrane has a higher antifouling effect. The antimicrobial properties of the PBM membrane contributed by polymerisable cationic surfactant acryloyloxyundecyltriethylammonium bromide (AUTEAB) guaranteed an anti-biofouling effect preventing the growth of microorganisms on the membrane surface. In addition, the PBM MBR module showed 10±1% higher blue dye removal efficiency and a similar rate of COD removal efficiency of about 95±1% compared to commercial module. However, water permeability was slightly lower due to extra resistance of the PBM coating. Root mean squared (RMS) roughness measurement and analysis of AFM images confirmed that the stable novel membrane coating still existed and showed antimicrobial effect even after 105 days of operation. The results obtained demonstrated the potential of the low fouling PBM membrane.European Union within BioNexGen project (CP-FP-246039-2 EU-FP7
Design and testing of a pilot-scale submerged membrane bioreactor (MBR) for textile wastewater treatment
Abstract The objective of this paper is to deal with the design of a pilot-scale submerged membrane bioreactor (MBR) and a short-term functionality test to be performed with textile wastewater. The design calculations were done based on the design parameters analysed from local textile wastewater and typical values of activated sludge kinetic coefficients. Other process parameters like bioreactor volume (tank size), hydraulic residence time (HRT), biomass loading (F/M ratio), oxygen demand, etc., were calculated depending on the real textile wastewater characteristics. Taking the design basis into consideration, a pilot-scale MBR was constructed equipped with LabVIEW programme- and sensors-controlled computer system. Based on the theoretical calculations, the hydraulic volume of the MBR reactor was around 56.6 L with flat sheet membranes (3 sheets, with 25 cm × 25 cm dimensions of each sheet) with HRT of 16.9 h. Finally, performance tests for 6 weeks were carried out in a local (Darmstadt, Germany) laundry textile wastewater to test the functionality of MBR pilot plant. Under the operating conditions of 250 mbar suction pressure and 12 g/L of MLSS, the COD removal efficiency was around 90% for 800–3500 mg/L inlet COD fed to the membrane bioreactor
New Polymeric Films with Antibacterial Activity Obtained by UV-induced Copolymerization of Acryloyloxyalkyltriethylammonium Salts with 2- Hydroxyethyl Methacrylate
- Article on the development of new polymeric films with antibacterial activity obtained by UV-induced copolymerization of some polymerizable surfactants (acryloyloxyalkyltriethylammonium bromides, in particular) with commercially available 2-hydroxyethyl methacrylate
- Raw data
Abstract of the paper: New polymeric films with antibacterial activity have been prepared, by simple
UV-induced copolymerization of readily available omega-(acryloyloxy)-N,N,N-triethylalcan-1-aminium
bromides (or acryloyloxyalkyltriethylammonium bromides, AATEABs) with commercially available
2-hydroxyethyl methacrylate (HEMA), at different relative amounts. In particular, the antibacterial
activity of polymeric films derived from 11-(acryloyloxy)-N,N,N-triethylundecan-1-aminium
bromide (or acryloyloxyundecyltriethylammonium bromide, AUTEAB; bearing a C-11
alkyl chain linker between the acrylate polymerization function and the quaternary
ammonium moiety) and 12-(acryloyloxy)-N,N,N-triethyldodecan-1-aminium bromide (or
acryloyloxydodecyltriethylammonium bromide, ADTEB, bearing a C-12 alkyl chain linker) has
been assessed against Gram-negative Escherichia Coli and Gram-positive Staphylococcus aureus cells.
The results obtained have shown a clear concentration-dependent activity against both bacterial
strains, the films obtained from homopolymerization of pure AUTEAB and ADTEAB being the most
e ective. Moreover, ADTEAB-based films showed a higher antibacterial activity with respect to the
AUTEAB-based ones. Interestingly, however, both types of films presented a significant activity not
only toward Gram-positive S. aureus, but also toward Gram-negative E. Coli cells
Expression of alternatively spliced variants of the Dclk1 gene is regulated by psychotropic drugs
Abstract Background The long-term effects of psychotropic drugs are associated with the reversal of disease-related alterations through the reorganization and normalization of neuronal connections. Molecular factors that trigger drug-induced brain plasticity remain only partly understood. Doublecortin-like kinase 1 (Dclk1) possesses microtubule-polymerizing activity during synaptic plasticity and neurogenesis. However, the Dclk1 gene shows a complex profile of transcriptional regulation, with two alternative promoters and exon splicing patterns that suggest the expression of multiple isoforms with different kinase activities. Results Here, we applied next-generation sequencing to analyze changes in the expression of Dclk1 gene isoforms in the brain in response to several psychoactive drugs with diverse pharmacological mechanisms of action. We used bioinformatics tools to define the range and levels of Dclk1 transcriptional regulation in the mouse nucleus accumbens and prefrontal cortex. We also sought to investigate the presence of DCLK1-derived peptides using mass spectrometry. We detected 15 transcripts expressed from the Dclk1 locus (FPKM > 1), including 2 drug-regulated variants (fold change > 2). Drugs that act on serotonin receptors (5-HT2A/C) regulate a subset of Dclk1 isoforms in a brain-region-specific manner. The strongest influence was observed for the mianserin-induced expression of an isoform with intron retention. The drug-activated expression of novel alternative Dclk1 isoforms was validated using qPCR. The drug-regulated isoform contains genetic variants of DCLK1 that have been previously associated with schizophrenia and hyperactivity disorder in humans. We identified a short peptide that might originate from the novel DCLK1 protein product. Moreover, protein domains encoded by the regulated variant indicate their potential involvement in the negative regulation of the canonical DCLK1 protein. Conclusions In summary, we identified novel isoforms of the neuroplasticity-related gene Dclk1 that are expressed in the brain in response to psychotropic drug treatments
Modular desalination concept with low-pressure reverse osmosis and capacitive deionization: Performance study of a pilot plant in Vietnam in comparison to seawater reverse osmosis
Membrane capacitive deionization (MCDI) has shown many advances, however, its performance in combination with other treatment technologies has not been widely reported. In this study, a pilot-scale low-pressure reverse osmosis (LPRO) (FilmTec™ XLE-2540) with MCDI (CapDI© C17, Voltea) was developed and tested as a promising modular desalination system. The systems were evaluated individually at different salinities and tested together as a modular system. The study focused in the comparison to conventional seawater reverse osmosis (SWRO) (FilmTec™ SW30-2540) at pilot-scale and in theory using the software Water Application Value Engine (WAVE, DuPont™), including a cost evaluation of the systems. Pilot tests were carried out in Can Gio, a riverine estuary region in South Vietnam, which is affected by progressive salinization (TDS ≈ 1–25 g/L). Drinking water quality (TDS < 600 mg/L) was achieved with a specific energy consumption (SEC) of 5.2 kWh/m³. Additionally, fouling mitigation was investigated for the ultrafiltration (UF) pre-treatment by periodic hydraulic and chemical enhanced backwashing. While the SWRO had a slightly lower SEC of 5.0 kWh/m³, WAVE calculations showed that lowering the SEC to 3.6 kWh/m³ is possible by improving the LPRO pump design and an optimization of the MCDI operation.Post-print / Final draf
Modeling of soil salinity in Rheris Oasis (Southeastern of Morocco) using satellite spectral indices
The Rheris oases in Southeastern Morocco are an essential ecosystem. It presents enormous ecological and natural values. Water scarcity coupled with agricultural intensification results in soil salinization and its degradation. This work aims to propose a spatiotemporal monitoring method of soil salinization in the Rheris oasis using spectral indices derived from Thematic Mapper (TM) and Operational Land Imager (OLI) data. The most used indices in the literature were (14 indices) tested and correlated with the results obtained from 50 samples taken from the first soil horizon at a constant depth of 0.20 m from the November 2022 campaign. The findings confirm that this method is highly effective and reliable for the modeling and spatial mapping of soil salinity in this region. The state of the hydroclimate is an aspect that influences soil salinization. An increase in salinized surfaces is observed during the periods of 1990–1996, 2000–2005, and 2017-2022. The spatio-temporal distribution of saline soils in Rheris Oasis is very variable. The monthly variations are more important than the annual ones
Déclaration d'Errachidia et lignes directrices pour le développement durable des écosystèmes oasiens.
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