filtration efficiency
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Portable household air purifiers are widely used devices designed to maintain a high-quality level of indoor air. Portable air purifiers equipped with the high-efficiency air (HEPA) filter served 100 h in a household space occupied by two adults without any symptoms of respiratory tract infection. The main objective of the study was to determine microbial contamination on the HEPA filter and to investigate if the selected nanotextile monolayer made of polyamide 6 (PA6) nanofibers can capture potential microorganisms when installed downstream of the HEPA filter as the final filtration medium. Samples were taken from the inlet and outlet surfaces. Samples from the nanotextile were collected in the same manner as from the HEPA filter. QIAStat DX® 1.0 Analyzer using the Respiratory SARS CoV-2 Panel multiplex PCR detection system was selected for microorganism detection. Adenovirus was detected on the inlet surface of the HEPA filter. The outlet surface of the filter contained no viruses included in the Respiratory SARS CoV-2 Panel portfolio. The nanotextile monolayer was replaced twice during the 100 h of operation, so three pieces were used and all contained coronavirus 229 E. Coronavirus 229 E was then detected in the nasopharynx of one of the members of the household as well. It may be assumed that the selected nanotextile is capable of capturing a virus of a small size.
- MeSH
- filtrace MeSH
- lidé MeSH
- pilotní projekty MeSH
- SARS-CoV-2 MeSH
- syndrom akutního respiračního selhání * MeSH
- vzduchové filtry * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
A study of new pig manure treatment and filtration process was carried out. The advantage of the worked out technology is the method of incorporation of crystalline phase into solid organic part of manure. The obtained new solid phase of manure contains about 50% of crystalline phase forming a filtration aid that enables high effectiveness of manure filtration. The filtration rate of manure separation into solid and liquid fractions with pressure filter may achieve 1300-3000 kg/m(2)/h. The method makes it possible to maintain an overall average pollutant removal performance 90% for the chemical oxygen demand COD, > 99% for the suspended solids SS, to 47% for the total nitrogen content. The obtained results showed that the proposed technology being efficient and simple offers a possible solution to pig manure problems.
- MeSH
- anaerobióza MeSH
- filtrace * MeSH
- hnůj * MeSH
- prasata MeSH
- průmyslová hnojiva * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Trace analysis of microorganisms in real biological samples needs very sensitive methods for their detection. Most procedures for detecting and quantifying pathogens require a sample preparation step including concentrating microorganisms from large sample volumes with high and reproducible efficiency. Electromigration techniques have great potential to include the preconcentration, separation, and detection of whole cells and therefore they can rapidly indicate the presence of pathogens. The preconcentration and separation of microorganisms from real suspensions utilising a combination of filtration and capillary isoelectric focusing was developed and the possibility for its application to real samples was verified. For our experiments, spores of Monilinia species and of Penicillium expansum were selected as model bioparticles, as they cause major losses in agrosystems. The isoelectric points of the spores of M. laxa, M. fructigena, M. fruticola, and P. expansum were determined and the method was verified using real samples taken directly from infected apples. The coupling of a filtration cartridge with a separation capillary can improve the detection limit of isoelectric focusing with UV detection by at least 4 orders of magnitude. Spores of M. fructigena and of M. laxa in numbers of hundreds of particles per milliliter were detected on a visually noninfected apple surface which was cross-contaminated during handling and storage. The efficiency of preconcentration and a preliminary identification was verified by the phenotyping technique after cultivation of the spores sampled from the apple surface.
- MeSH
- Ascomycota izolace a purifikace MeSH
- design vybavení MeSH
- elektroforéza kapilární přístrojové vybavení metody MeSH
- filtrace přístrojové vybavení metody MeSH
- isoelektrická fokusace přístrojové vybavení metody MeSH
- Malus mikrobiologie MeSH
- Penicillium izolace a purifikace MeSH
- senzitivita a specificita MeSH
- spory hub izolace a purifikace MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- práce podpořená grantem MeSH
The purpose of calculating the capillary filtration coefficient is to experimentally evaluate edema formation in models of pulmonary ischemia-reperfusion injury. For many years, the obtaining of this coefficient implies a series of manual maneuvers during ex-vivo reperfusion of pulmonary arterial pressure, venous pressure and weight, as well as the calculation of the Kfc formula. Through automation, the calculation of capillary filtration coefficient could be easier and more efficient. To describe an automatic method designed in our laboratory to calculating the capillary filtration coefficient and compare with traditional determination of capillary filtration coefficient as gold standard method. An automatic three valve perfusion system was constructed, commanded by a mastery module connected to a graphical user interface. To test its accuracy, cardiopulmonary blocks of Wistar rats were harvested and distributed in manual (n=8) and automated (n=8) capillary filtration coefficient determination groups. Physiological parameters as pulmonary arterial pressure, pulmonary venous pressure, weight and capillary filtration coefficient were obtained. Results: Capillary filtration coefficient, pulmonary arterial pressure, venous arterial pressure shown no statistical significance difference between the groups. The automated perfusion system for obtaining Kfc was standardized and validated, giving reliable results without biases and making the process more efficient in terms of time and personal staff.
- MeSH
- arteria pulmonalis fyziologie MeSH
- kapilární permeabilita fyziologie MeSH
- kapiláry fyziologie MeSH
- krysa rodu rattus MeSH
- orgánové kultury - kultivační techniky MeSH
- perfuze přístrojové vybavení metody MeSH
- plicní tlak v zaklínění fyziologie MeSH
- potkani Wistar MeSH
- venae pulmonales fyziologie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
A high-performance liquid chromatography method using an alternative pentafluorophenyl (PFP) core-shell stationary phase has been developed and used for rapid separation of 23 anthocyanins in a highbush blueberry Bluehaven cultivar. A high efficiency of separation of anthocyanins was achieved in the core-shell column Kinetex PFP, 150×4.6mm (particle size 2.6µm) with a 5×4.6mm precolumn, using a simple linear gradient elution with a mobile phase of acetonitrile and a water solution of 2% formic acid at a flow rate of 1.0ml/min and at a temperature of 50°C. The detection wavelength was set at 520nm for detection of all anthocyanins. The homogenized blueberry sample (Bluehaven cultivar) was extracted using pure methanol with 1.3% formic acid using an ultrasound bath for 20min and then filtrated. A 5-µL sample volume was directly injected into the HPLC system. The developed method showed an efficient separation of 23 anthocyanins in a total runtime of 21min. The potential of the pentafluorophenyl phase for efficient separation was demonstrated on a wide range of anthocyanins varying in glycosylation and acylation patterns found in highbush blueberries. The fluorinated stationary phase showed an alternative and complementary separation approach providing unique aromatic and polar selectivity in comparison with common C-18 phases.
Shredded card (SC) was assessed for use as a sorbent of potentially toxic elements (PTE) carried from contaminated soil in various leachates (oxalic acid, formic acid, CaCl2, water). We further assessed SC for retention of PTE, using acidified water (pH 3.4). Vertical columns and a peristaltic pump were used to leach PTE from soils (O and A/B horizons) before passing through SC. Sorption onto SC was studied by comparing leachates, and by monitoring total PTE contents on SC before and after leaching. SC buffers against acidic soil conditions that promote metals solubility; considerable increases in solution pH (+4.49) were observed. Greatest differences in solution PTE content after leaching with/without SC occurred for Pb. In oxalic acid, As, Cd, Pb showed a high level of sorption (25, 15, and 58x more of the respective PTE in leachates without SC). In formic acid, Pb sorption was highly efficient (219x more Pb in leachate without SC). In water, only Pb showed high sorption (191x more Pb in leachate without SC). In desorption experiments, release of PTE from SC varied according to the source of PTE (organic/mineral soil), and type of solvent used. Arsenic was the PTE most readily leached in desorption experiments. Low As sorption from water was followed by fast release (70% As released from SC). A high rate of Cd sorption from organic acid solutions was followed by strong retention (~12% Cd desorption). SC also retained Pb after sorption from water, with subsequent losses of ≤8.5% of total bound Pb. The proposed use of this material is for the filtration of PTE from extract solution following soil washing. Low-molecular-mass organic acids offer a less destructive, biodegradable alternative to strong inorganic acids for soil washing.
- MeSH
- arsen chemie MeSH
- filtrace metody MeSH
- kadmium chemie MeSH
- látky znečišťující půdu chemie MeSH
- monitorování životního prostředí MeSH
- olovo chemie MeSH
- organické látky MeSH
- roztoky chemie MeSH
- těžké kovy chemie MeSH
- znečištění životního prostředí prevence a kontrola MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The aim of this study was to investigate the suitability of a novel electrospun polyurethane nanofibre material for water-treatment purposes. Bacterial removal efficiency was tested in the laboratory by filtering artificial water spiked with Escherichia coli through a 0.25 µm nanofibre membrane. The results were compared with those obtained using a commercial microfiltration material (MV020T) with a similar pore size (0.20 µm). Alongside the laboratory experiments, we also determined filtration efficiency with semi-pilot scale experiments using actual wastewater from the secondary sedimentation tank of a wastewater treatment plant. The laboratory experiments indicated very high log10 removal efficiency, ranging from 5.8 to 6.8 CFU (colony-forming units)/ml. These results were better than those of the commercial membrane (3.8-4.6 CFU/ml). The semi-pilot scale experiment confirmed the membrane's suitability for microbial filtration, with both E. coli and total culturable microorganisms (cultured at both 22 and 36 °C) showing a significant decline compared to the non-filtered control (wastewater from the secondary outlet).
- MeSH
- čištění vody přístrojové vybavení MeSH
- Escherichia coli MeSH
- filtrace přístrojové vybavení MeSH
- membrány umělé * MeSH
- nanovlákna * MeSH
- pilotní projekty MeSH
- polyurethany chemická syntéza MeSH
- povidon MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- práce podpořená grantem MeSH
