RESUMEN
Selenium nanoparticles (SeNPs) are used in several sectors as antitumor, antimicrobial, and environmental adsorbents. Thus, the present research objective was the production of bacterial-SeNPs as an active and environmentally-friendly antibacterial and adsorbent agents and application into novel nanocomposite filter. From a total of 25 samples (soil, wastewater, and water) obtained from different locations in Egypt, 60 selenium-resistant bacterial isolates were obtained (on a mineral salt medium supplemented with selenium ions). After screening (based on the conversion of selenium from ionic form to nanoform), a superior bacterial isolate for SeNPs formation was obtained and molecular identified as Bacillus pumilus isolate OR431753. The high yield of SeNPs was noted after optimization (glucose as carbon source, pH 9 at 30 °C). The produced SeNPs were characterized as approximately 15 nm-diameter spherical nanoparticles, in addition to the presence of organic substances around these particles like polysaccharides and aromatic amines (protein residues). Also, they have antibacterial activity increased after formation of nanocomposite with nano-chitosan (SeNPs/NCh) against several pathogens. The antibacterial activity (expressed as a diameter of the inhibitory zone) averaged between 2.1 and 4.3, 2.7 and 4.8 cm for SeNPs and SeNPs/NCh, respectively compared with 1.1 to 1.8 cm for Amoxicillin. The produced nanoselenium/chitosan was used as a biofilter to remove mercury (Hg) and AgNPs as model chemicals with serious toxicity and potential pollutant for water bodies in many industries. The new SeNPs/NCh biofilter has proven highly effective in individually removing mercury and AgNPs from their synthetic wastewaters, with an efficiency of up to 99%. Moreover, the removal efficiency of AgNPs stabilized at 99% after treating them with the syringe filter-Se nanocomposite for 4 cycles of treatment (5 min each).
Asunto(s)
Biodegradación Ambiental , Mercurio , Nanocompuestos , Selenio , Plata , Aguas Residuales , Purificación del Agua , Aguas Residuales/química , Nanocompuestos/química , Selenio/química , Mercurio/química , Mercurio/aislamiento & purificación , Purificación del Agua/métodos , Plata/química , Contaminantes Químicos del Agua/química , Nanopartículas del Metal/química , Antibacterianos/farmacología , Antibacterianos/química , Desinfección/métodos , Filtración/métodos , Bacillus/metabolismo , Bacillus/efectos de los fármacos , Quitosano/química , Quitosano/farmacologíaRESUMEN
The high water consumption in agriculture has led to an obvious water crisis in this sector, and the use of unconventional water sources, especially agricultural drains, is considered necessary. For this purpose, the present study was carried out to evaluate the efficiency of biological filters with different types of substrates for treating agricultural wastewater in Khuzestan province, located in the south of Iran, to use receptive resources and reuse them in agriculture. Next, the efficiency of four types of biological filters for treating agricultural drainage water with different retention times was evaluated. Sawdust, cotton stalks, wheat straw, stubble, and rice husk were used as filters. Qualitative factors included agricultural pesticides (Atrazine, Randup, Paraquat, and 2, 4-D) and nutrients (nitrate, nitrogen, phosphate, and phosphorus). By examining the trend of increasing the retention time and the corresponding removal percentage, it was observed that the retention time has a direct relationship with the amount of removal efficiency of nutrients and agricultural toxins. As the residence time increases, the average amount of nutrient compounds in different filters decreases, and their removal percentage increases. The highest removal percentage of nitrate, total nitrogen, phosphate, and total phosphorus was 74.03, 71.66, 57.97, and 61.85% in the sawdust filter and was assigned to 10 days. The highest percentage of removal of Atrazine, Tofudi, Paraquat, and Roundup toxins with a removal efficiency of 91.73, 84.27, 89.81, and 88.46% was also observed in the treatment of sawdust for 10 days. The sawdust filter showed a good performance in removing the parameters of agricultural toxins and nutrient compounds in a retention time of 10 days compared to other filters and retention times. As a general result, the sawdust filter can be cited as a reliable substrate with acceptable efficiency compared to other filters.
Asunto(s)
Agricultura , Filtración , Plaguicidas , Contaminantes Químicos del Agua , Purificación del Agua , Agricultura/métodos , Plaguicidas/aislamiento & purificación , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Filtración/métodos , Fósforo/análisis , Fósforo/aislamiento & purificación , Nitrógeno/análisis , Nitrógeno/aislamiento & purificación , Aguas Residuales/química , Nutrientes/análisis , Irán , Nitratos/análisis , Nitratos/aislamiento & purificación , Fosfatos/análisis , Fosfatos/aislamiento & purificaciónRESUMEN
Introduction: Exposure to harmful aerosols is of increasing public health concern due to the SARS-CoV-2 pandemic and wildland fires. These events have prompted risk reduction behaviors, notably the use of disposable respiratory protection. This project investigated whether craniofacial morphology impacts the efficiency of disposable masks (N95, KN95, surgical masks, KF94) most often worn by the public to protect against toxic and infectious aerosols. This project was registered with ClinicaltTrials.gov (NCT05388201; registration May 18, 2022). Methods: One-hundred participants (50 men, 50 women) visited the Environmental Protection Agency's Human Studies Facility in Chapel Hill, NC between 2022-2023. Craniometrics and 3D scans were used to separate participants into four clusters. Boosting and elastic net regression yielded five measurements (bizygomatic breadth, nose length, bizygomatic nasal arc, neck circumference, ear breadth) that were the best predictors of filtration efficiency based on overall model fit. Fitted filtration efficiency was quantified for each mask at baseline and when tightened using an ear-loop clip. Results: The mean unmodified mask performance ranged from 55.3% (15.7%) in the large KF94 to 69.5% (12.3%) in the KN95. Modified performance ranged from 66.3% (9.4%) in the surgical to 80.7% (12.0%) in the KN95. Clusters with larger face width and neck circumference had higher unmodified mask efficiency. Larger nose gap area and nose length decreased modified mask performance. Discussion: We identify face width, nose size, nose shape, neck circumference, and ear breadth as specific features that modulate disposable mask fit in both unmodified and modified conditions. This information can optimize guidance on respiratory protection afforded by disposable ear-loop masks.
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Equipos Desechables , Filtración , Máscaras , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Aerosoles , Cefalometría , Diseño de Equipo , Filtración/instrumentación , Dispositivos de Protección RespiratoriaRESUMEN
Nanofiltration (NF) technology is pivotal for ensuring a sustainable and reliable supply of clean water. To address the critical need for advanced thin-film composite (TFC) polyamide (PA) membranes with exceptional permselectivity and fouling resistance for emerging contaminant purification, we introduce a novel high-performance NF membrane. This membrane features a selective polypiperazine (PIP) layer functionalized with amino-containing quaternary ammonium compounds (QACs) through an in situ interfacial polycondensation reaction. Our investigation demonstrated that precise QAC functionalization enabled the construction of the selective PA layer with increased surface area, enhanced microporosity, stronger electronegativity, and reduced thickness compared to the control PIP membrane. As a result, the QAC NF membrane exhibited an approximately 51% increase in water permeance compared to the control PIP membrane, while achieving superior retention capabilities for divalent salts (>99%) and emerging organic contaminants (>90%). Furthermore, the incorporation of QACs into the PIP selective layer was proved to be effective in mitigating mineral scaling by allowing selective passage of scale-forming cations, while simultaneously exhibiting strong antimicrobial properties to combat biofouling. The in situ QAC incorporation strategy presented in this study provides valuable guidelines for the fit-for-purpose design of the selective PA layer, which is crucial for the development of high-performance NF membranes for efficient water purification.
Asunto(s)
Incrustaciones Biológicas , Filtración , Membranas Artificiales , Purificación del Agua , Purificación del Agua/métodos , Sulfato de Calcio/química , Nylons/químicaRESUMEN
The growing production and use of plastics significantly contribute to microplastics (MPs) contamination in the environment. Humans are exposed to MPs primarily through the gastrointestinal route, as these particles are present in beverages and food, e.g., sugar. Effective isolation and identification of MPs from food is essential for their elimination. This study aimed to evaluate factors influencing the isolation of MPs from sucrose solutions to determine optimal conditions for the process. Polyethylene particles were used to test separation methods involving chemical digestion with acids and filtration through membrane filters made of nylon, mixed cellulose ester, and cellulose acetate with pore sizes of 0.8 and 10 µm. The effects of temperature and acid type and its concentration on plastic particles were examined using scanning electron microscopy and µ-Raman spectroscopy. The results indicate that increased temperature reduces solution viscosity and sucrose adherence to MPs' particles, while higher acid concentrations accelerate sucrose hydrolysis. The optimal conditions for MPs' isolation were found to be 5% HCl at 70 °C for 5 min, followed by filtration using an efficient membrane system. These conditions ensure a high recovery and fast filtration without altering MPs' surface properties, providing a reliable basis for further analysis of MPs in food.
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Microplásticos , Sacarosa , Sacarosa/química , Microplásticos/química , Microplásticos/análisis , Filtración/métodos , Temperatura , Polietileno/química , ViscosidadRESUMEN
The present study investigated the impact of filtration, creaming and pasteurization on the authentication of the botanical origin of honey using the dilute-and-shoot method in liquid chromatography coupled to mass spectrometry (LC-MS). The analytical method performances were satisfactory (analyte recoveries ranging from 95 % to 103 % and inter-day precision below 12 %). Three types of raw honeys including blueberry, canola and clover were processed under controlled conditions. Filtration, creaming and pasteurization had no impact on honey botanical classification based on the LC-MS fingerprint, and the key molecular fingerprints were retained after processing. However, results revealed that testing the impact of processing is essential when selecting honey authenticity markers because some candidates (e.g. adenosine) are not stable or can be removed during honey processing. The results of the present study also highlighted the suitability of the dilute-and-shoot approach to both develop authentication tools for honey and study the impact of processing methods on specific chemicals in honeys.
Asunto(s)
Filtración , Manipulación de Alimentos , Miel , Pasteurización , Miel/análisis , Miel/clasificación , Pasteurización/métodos , Cromatografía Liquida/métodos , Manipulación de Alimentos/métodos , Espectrometría de Masas/métodos , Contaminación de Alimentos/análisisRESUMEN
Nanofiltration (NF) has been used as the default sulfate removal process in platforms to treat seawater for water flooding. Seawater is generally pretreated by chlorination and cartridge filters to reduce fouling of the membranes; however, this pretreatment is insufficient to provide water quality high enough to maintain the productivity of the NF membranes. In this study, the performances of two different pretreatment routes were evaluated. Microfiltration (MF) was evaluated as a replacement for cartridge filters, and the advanced oxidation process UV/H2O2 was evaluated as an additional stage of pretreatment upstream of the cartridge filters. The permeability of the NF membranes after 12 h of seawater sulfate removal in a bench system was 4.4 L·h-1·m-2·bar-1 when the UV/H2O2 process was adopted as the pretreatment and 2.9 L·h-1·m-2·bar-1 when the MF process was adopted, compared to 1.6 L·h-1·m-2·bar-1 achieved for the pretreatment with the cartridge filter alone. These results indicate that NF membrane fouling was significantly higher when seawater was pretreated only by the cartridge filter in comparison to both proposed pretreatments. An economic analysis showed that both systems are economically viable and can potentially reduce the operational costs of the NF sulfate removal process on platforms.
Asunto(s)
Filtración , Agua de Mar , Purificación del Agua , Purificación del Agua/métodos , Purificación del Agua/instrumentación , Filtración/métodos , Filtración/instrumentación , Membranas Artificiales , Sulfatos/química , Nanotecnología , Peróxido de Hidrógeno/químicaRESUMEN
Bank filtration supports the growing global demand for drinking water amidst concerns over organic micropollutants (OMPs). Efforts to investigate, regulate and manage OMPs have intensified due to their documented impacts on ecosystems and human health. Non-targeted analysis (NTA) is critical for addressing the challenge of numerous OMPs. While identification in NTA typically prioritises compounds based on properties like toxicity, considering substance quantity, occurrence frequency and exposure duration is essential for comprehensive risk management. A prioritisation scheme, drawing from intensive sampling and NTA of bank filtrate, is presented and reveals significant variability in OMP occurrence. Quasi-omnipresent substances, though only 7% of compounds, accounted for 44% of cumulative detections. Moderately common substances, constituting 31% of compounds, accounted for 50% of cumulative detections. Rare compounds, comprising 61%, contributed only 6% to cumulative detections. The application of suspect screening for 31 substances to the dataset yielded results akin to NTA, underscoring NTA's value. Correlation between both methods demonstrates the efficacy of high-resolution mass spectrometry-based NTA in assessing temporal and quantitative OMP dynamics.
Asunto(s)
Monitoreo del Ambiente , Filtración , Ríos , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Ríos/química , Flujo de TrabajoRESUMEN
In Flanders, an estimated 300,000 leukoreduction filters are discarded as biological waste in the blood establishment each year. These filters are a possible source of fresh donor leukocytes for downstream purposes including research. We investigated leukocyte isolation from two types of filters either used for the preparation of platelet concentrates (PC-LRF) or erythrocyte concentrates (EC-LRF). Outcome parameters were leukocyte yield, differential count, turnaround time and effect of storage conditions. Leukocytes were harvested by reverse flow of a buffer solution. Control was the gold standard density gradient centrifugation of buffy coats. Total leukocyte number isolated from PC-LRF (1049 (± 40) x 106) was almost double that of control (632 (± 66) x 106) but the differential count was comparable. Total leukocyte number isolated from EC-LRF (78 (± 9) x 106) was significantly lower than control, but the sample was specifically enriched in granulocytes (81 ± 4%) compared to control (30 ± 1%). Isolation of leukocytes from either PC- or EC-LRF takes 20 min compared to 240 min for control density gradient centrifugation. Leukocyte viability is optimal when harvested on day 1 post donation (95 ± 0.9%) compared to day 3 (76.4 ± 2.4%). In conclusion, our study demonstrates that leukoreduction filters from specific blood component processing are easy to use and present a valuable source for viable leukocytes of all types.
Asunto(s)
Procedimientos de Reducción del Leucocitos , Leucocitos , Humanos , Procedimientos de Reducción del Leucocitos/instrumentación , Procedimientos de Reducción del Leucocitos/métodos , Leucocitos/citología , Recuento de Leucocitos , Eritrocitos/citología , Centrifugación por Gradiente de Densidad/métodos , Supervivencia Celular , Plaquetas/citología , Filtración/instrumentación , Filtración/métodos , Factores de TiempoRESUMEN
Nanofiltration (NF) membranes play a critical role in separation processes, necessitating an in-depth understanding of their selective mechanisms. Existing NF models predominantly include steric and Donnan mechanisms as primary mechanisms. However, these models often fail in elucidating the NF selectivity between ions of similar dimensions and the same valence. To address this gap, an innovative methodology was proposed to unravel new selective mechanisms by quantifying the nominal dielectric effect isolated from steric and Donnan exclusion through fitted pore dielectric constants by regression analysis. We demonstrated that the nominal dielectric effect encompassed unidentified selective mechanisms of significant relevance by establishing the correlation between the fitted pore dielectric constants and these hindrance factors. Our findings revealed that dehydration-induced ion-membrane interaction, rather than ion dehydration, played a pivotal role in ion partitioning within NF membranes. This interaction was closely linked to the nondeformable fraction of hydrated ions. Further delineation of the dielectric effect showed that favorable interactions between ions and membrane functional groups contributed to entropy-driven selectivity, which is a key factor in explaining ion selectivity differences between ions sharing the same size and valence. This study deepens our understanding of NF selectivity and sheds light on the design of highly selective membranes for water and wastewater treatment.
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Filtración , Iones , Purificación del Agua/métodos , Membranas Artificiales , NanotecnologíaRESUMEN
Digestates from low-tech digesters need to be post-treated to ensure their safe agricultural reuse. This study evaluated, for the first time, vermifiltration as a post-treatment for the digestate from a low-tech digester implemented in a small-scale farm, treating cattle manure and cheese whey under psychrophilic conditions. Vermifiltration performance was monitored in terms of solids, organic matter, nutrients, and pathogens removal efficiency. In addition, the growth of earthworms (Eisenia foetida) and their role in the process was evaluated. Finally, the vermicompost and the effluent of the vermifilter were characterized in order to assess their potential reuse in agriculture. Vermifilters showed high removal efficiency of chemical oxygen demand (55-90%), total solids (60-80%), ammonium nitrogen (83-97%), and phosphate-P (28-49%). Earthworms effectively grew and reproduced on digestate (i.e. earthworms number increased by 183%), enhancing the vermifiltration performance, while reducing clogging and odour-related issues. Both the vermicompost and effluent produced complied with legislation limits established for soil improvers and wastewater for fertigation, respectively. Indeed, there was an absence of pathogens and non-detectable heavy metals concentrations. Vermifiltration may be thus considered a suitable post-treatment option for the digestate from low-tech digesters, allowing for its safe agricultural reuse and boosting the circular bioeconomy in small-scale farms.
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Agricultura , Estiércol , Oligoquetos , Animales , Granjas , Suelo , Bovinos , Análisis de la Demanda Biológica de Oxígeno , Filtración , Aguas Residuales/químicaRESUMEN
Nutrient pollution has become an important issue to solve in stormwater runoff due to the fast population growth and urbanization that impacts water quality and triggers harmful algal blooms. There is an acute need to link the dissolved organic nitrogen (DON) decomposition with the coupled nitrification and denitrification pathways to realize the pattern shifts in the nitrogen cycle. This paper presented a lab-scale cascade upflow biofiltration system for comparison of nitrate and phosphate removal from stormwater matrices through two specialty adsorbents at three influent conditions. The two specialty adsorbents are denoted as biochar iron and perlite integrated green environmental media (BIPGEM) and zero-valent iron and perlite-based green environmental media (ZIPGEM). An initial condition with stormwater runoff, a second condition with spiked nitrate, and a third condition with spiked nitrate and phosphate were used in this study. To differentiate nitrifier and denitrifier population dynamics associated with the decomposition of DON, integrative analysis of quantitative polymerase chain reaction (qPCR) and 21 tesla Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) were performed in association with nitrate removal efficiencies for both media with or without the presence of phosphate. While the qPCR may detect one gene for a single microbe or pathogen and realize the microbial population dynamics in the bioreactors, the 21 T FT-ICR MS can separate and assign elemental compositions to identify organic compounds of DON. Results indicated that ZIPGEM obtained a higher potential for nutrient removal than BIPGEM when the influent was spiked with nitrate and phosphate simultaneously. The sustainable, scalable, and adaptable upflow bioreactors operated in sequence (in a cascade mode) can be expanded flexibly on an as-needed basis to meet the local water quality standards showing process reliability, resilience, and sustainability simultaneously.
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Filtración , Nitrógeno , Nitratos , Purificación del Agua/métodos , Desnitrificación , Contaminantes Químicos del Agua , FosfatosRESUMEN
This work proposed a simple and ultrasensitive nanozyme-based immunoassay on a filtration device for the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleocapsid protein (NP). Gold core porous platinum shell nanoparticles (Au@Pt NPs) were synthesized with high catalytic activity to oxidize 3,3',5,5'-tetramethylbenzidine, leading to an oblivious color change. The filtration device was designed based on the size difference of magnetic beads, filter membrane pore, and Au@Pt NPs. A simple, rapid, and consistent washing procedure can be performed with the help of a plastic syringe. This detection method could realize the quantitative detection of SARS-CoV-2 NP within 80 min for point-of-care needs. The limit of detection for the SARS-CoV-2 antigen was 0.01 ng/mL in buffer. The coefficients of variation of the assay were 1.78% for 10 ng/mL SARS-CoV-2 antigen, 2.03% for 1 ng/mL SARS-CoV-2 antigen, and 2.34% for the negative sample, respectively. The specificity of the detection platform was verified by the detection of various respiratory viruses. This simple and effective detection system was expected to promote substantial progress in the development and application of virus immunodetection technology.
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COVID-19 , Oro , Nanopartículas del Metal , SARS-CoV-2 , SARS-CoV-2/aislamiento & purificación , SARS-CoV-2/inmunología , Humanos , COVID-19/diagnóstico , COVID-19/virología , Oro/química , Nanopartículas del Metal/química , Filtración/instrumentación , Platino (Metal)/química , Proteínas de la Nucleocápside de Coronavirus/inmunología , Límite de Detección , Inmunoensayo/métodos , Inmunoensayo/instrumentación , Jeringas , Antígenos Virales/análisis , Antígenos Virales/inmunología , Bencidinas/química , Inmunoadsorbentes/química , FosfoproteínasRESUMEN
Small extracellular vesicles (sEVs) are proven to hold great promise for diverse therapeutic and diagnostic applications. However, batch preparation of sEVs with high purity and bioactivity is a prerequisite for their clinical translations. Herein, we present an electric field assisted tangential flow filtration system (E-TFF), which integrates size-based filtration with electrophoretic migration-based separation to synergistically achieve the isolation of high-quality sEVs from cell culture medium. Compared with the gold-standard ultracentrifugation (UC) method, E-TFF not only improved the purity of sEVs by 1.4 times but also increased the yield of sEVs by 15.8 times. Additionally, the entire isolation process of E-TFF was completed within 1 h, about one-fourth of the time taken by UC. Furthermore, the biological activity of sEVs isolated by E-TFF was verified by co-incubation of sEVs derived from human umbilical cord mesenchymal stem cells (hUCMSCs) with HT22 mouse hippocampal neuronal cells exposed to amyloid-ß (Aß). The results demonstrated that the sEVs isolated by E-TFF exhibited a significant neuroprotective effect. Overall, the E-TFF platform provides a promising and robust strategy for batch preparation of high-quality sEVs, opening up a broad range of opportunities for cell-free therapy and precision medicine.
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Vesículas Extracelulares , Filtración , Vesículas Extracelulares/química , Vesículas Extracelulares/metabolismo , Animales , Ratones , Humanos , Filtración/instrumentación , Filtración/métodos , Células Madre Mesenquimatosas/citología , Medios de Cultivo/química , Péptidos beta-Amiloides/metabolismo , Línea CelularRESUMEN
To protect occupants in vehicle cabin environments from the health risks of high concentrations of particulate matter (PM), it is important to install vehicle cabin air filter (VCAF) to eliminate PM. In this study, we investigated the filtration performance of 22 VCAFs. Results showed that the minimum average filtration efficiency was 56.1 % for particles with a diameter of 0.1-0.3 µm, a pressure drop of 33.2-250 Pa at air velocity of 2.5 m/s, and the dust-holding capacity ranged from 5.8 to 19.4 g. In addition, as the filter area increased from 0.23 m2 to 0.50 m2, the filtration efficiency for particles with a diameter of 0.1-0.3 µm increased from 56.7 % to 77.5 %, the pressure drop decreased from 96.1 to 62.5 Pa, and the dust holding capacity increased 2.7 times. Furthermore, we compared the service life of VCAF from 31 major Chinese cities and found that the service life varied greatly from maximum of 1730 h for Haikou to minimum of 352 h for Shijiazhuang. Considering occupant health risks, Beijing requires that VCAFs have PM2.5 filtration efficiency at least 88.1 %, and Liaoning requires minimum of 97.5 %. Hence, choosing the appropriate VCAF based on the atmospheric environment of different cities deserves our attention.
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Filtros de Aire , Filtración , Material Particulado , China , Material Particulado/análisis , Contaminantes Atmosféricos/análisis , Tamaño de la Partícula , Contaminación del Aire Interior/análisis , Contaminación del Aire Interior/prevención & control , Contaminación del Aire Interior/estadística & datos numéricos , Monitoreo del Ambiente , Polvo/análisis , Humanos , Ciudades , Contaminación del Aire/prevención & control , Contaminación del Aire/estadística & datos numéricos , Emisiones de Vehículos/análisis , AutomóvilesRESUMEN
Anaerobic Membrane Bioreactor (AnMBR) are employed for solid-liquid separation in wastewater treatment, enhancing process efficiency of digestion systems treating digestate. However, membrane fouling remains a primary challenge. This study operated a pilot-scale AnMBR (P-AnMBR) to treat high-concentration organic digestate, investigating system performance and fouling mechanisms. P-AnMBR operation reduced acid-producing bacteria and increased methane-producing bacteria on the membrane, preventing acid accumulation and ensuring stable operation. The P-AnMBR effectively removed COD and VFA, achieving removal rates of 82.3 % and 92.0 %, respectively. Higher retention of organic nitrogen and lower retention of ammonia nitrogen were observed. The membrane fouling consisted of organic substances (20.3 %), predominantly polysaccharides, and inorganic substances (79.7 %), primarily Mg ions (10.1 %) and Ca ions (4.5 %). To reduce the increased transmembrane pressure (TMP) caused by fouling (a 10.6-fold increase in filtration resistance), backwash frequency experiment was conducted. It revealed a 30-min backwash frequency minimized membrane flux decline, facilitating recovery to higher flux levels. The water produced amounted to 70.3 m³ over 52 days. The research provided theoretical guidance and practical support for engineering applications, offering practical insights for scaling up P-AnMBR.
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Reactores Biológicos , Membranas Artificiales , Eliminación de Residuos Líquidos , Anaerobiosis , Eliminación de Residuos Líquidos/métodos , Proyectos Piloto , Aguas Residuales/química , Purificación del Agua/métodos , Análisis de la Demanda Biológica de Oxígeno , Filtración , Metano/metabolismoRESUMEN
With widespread occurrence and increasing concern of emerging contaminants (CECs) in source water, biologically active filters (BAF) have been gaining acceptance in water treatment. Both BAFs and graphene oxide (GO) have been shown to be effective in treating CECs. However, studies to date have not addressed interactions between GO and microbial communities in water treatment processes such as BAFs. Therefore, in the present study, we investigated the effect of GO on the properties and microbial growth rate in a BAF system. Synthesized GO was characterized with a number of tools, including scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDX), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and Raman spectrometry. GO exhibited the characteristic surface functional groups (i.e., C-OH, C=O, C-O-C, and COOH), crystalline structure, and sheet-like morphology. To address the potential toxicity of GO on the microbial community, reactive oxygen species (ROS) generation was measured using nitro blue tetrazolium (NBT) assay. Results revealed that during the exponential growth phase, ROS generation was not observed in the presence of GO compared to the control batch. In fact, the adenosine triphosphate (ATP) concentrations increased in the presence of GO (25 µg/L - 1000 µg/L) compared to the control without GO. The growth rate in systems with GO exceeded the control by 20 % to 46 %. SEM images showed that GO sheets can form an effective scaffold to promote bacterial adhesion, proliferation, and biofilm formation, demonstrating its biocompatibility. Next-generation sequencing (Illumina MiSeq) was used to characterize the BAF microbial community, and high-throughput sequencing analysis confirmed the greater richness and more diverse microbial communities compared to systems without GO. This study is the first to report the effect of GO on the microbial community of BAF from a water treatment plant, which provides new insights into the potential of utilizing a bio-optimized BAF for advanced and sustainable water treatment or reuse strategies.
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Grafito , Purificación del Agua , Grafito/química , Purificación del Agua/métodos , Filtración , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Conductive nanofiltration (CNF) membranes hold great promise for removing small organic pollutants from water through enhanced Donnan exclusion and electrocatalytic degradation. However, current CNF membranes face limitations in conductivity, structural stability, and nanochannel control strategies. This work addresses these challenges by introducing aniline-functionalized carbon nanotubes (NH2-CNTs) as an interlayer. NH2-CNTs enhance the dispersibility and adhesion of pristine carbon nanotubes, leading to a more conductive and stable composite nanofiltration membrane. The redesigned NH2-CNTs interlayered conductive nanofiltration (NICNF) membrane exhibits a 10-fold increase in conductivity and a high response degree (80%) with excellent cyclic stability, surpassing existing CNF membranes. The synergistic effects of enhanced Donnan exclusion, voltage switching, and electrocatalysis enable the NICNF membrane to achieve selective recovery of mixed dyes, 98.97% removal of residual wastewater toxicity, and a 5.2-fold increase in permeance compared to the commercial NF270 membrane. This research paves the way for next-generation multifunctional membranes capable of the efficient recovery and degradation of toxic organic pollutants in wastewater.
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Filtración , Membranas Artificiales , Nanotubos de Carbono , Contaminantes Químicos del Agua , Nanotubos de Carbono/química , Contaminantes Químicos del Agua/química , Compuestos de Anilina/química , Aguas Residuales/química , Purificación del Agua/métodos , Conductividad EléctricaRESUMEN
Rapid and sensitive detection of pathogens in various samples is crucial for disease diagnosis, environmental surveillance, as well as food and water safety monitoring. However, the low abundance of pathogens (<10 CFU) in large volume (1 mL-1 L) samples containing vast backgrounds critically limits the sensitivity of even the most advanced techniques, such as digital PCR. Therefore, there is a critical need for sample preparation that can enrich low-abundance pathogens from complex and large-volume samples. This study develops an efficient electrostatic microfiltration (EM)-based sample preparation technique capable of processing ultra-large-volume (≥500 mL) samples at high throughput (≥10 mL min-1). This approach achieves a significant enrichment (>8000×) of extremely-low-abundance pathogens (down to level of 0.02 CFU mL-1, i.e., 10 CFU in 500 mL). Furthermore, EM-enabled sample preparation facilitates digital amplification techniques sensitively detecting broad pathogens, including bacteria, fungi, and viruses from various samples, in a rapid (≤3 h) sample-to-result workflow. Notably, the operational ease, portability, and compatibility/integrability with various downstream detection platforms highlight its great potential for widespread applications across diverse settings.
Asunto(s)
Filtración , Electricidad Estática , Filtración/instrumentación , Bacterias/aislamiento & purificación , Bacterias/genética , Virus/aislamiento & purificación , Hongos/aislamiento & purificaciónRESUMEN
Potentially health-promoting concentrations of flavan-3-ols were previously shown to be retained in apple juices produced with the emerging spiral filter press. Due to the novelty of this technology, the factors governing the stability of flavan-3-ol-rich apple juices have only scarcely been studied. Therefore, we produced flavan-3-ol-rich apple juices and concentrates (16, 40, 70 °Brix) supplemented with ascorbic acid (0.0, 0.2, 1.0 g/L) according to common practice. Flavan-3-ols (DP1-7) and twelve flavan-3-ol reaction products were comprehensively characterized and monitored during storage for 16 weeks at 20 and 37 °C, employing RP-UHPLC- and HILIC-DAD-ESI(-)-QTOF-HR-MS/MS. Flavan-3-ol degradation followed a second-order reaction kinetic, being up to 3.5-times faster in concentrates (70 °Brix) than in single strength juices (16 °Brix). Furthermore, they diminished substantially faster compared to other phenolic compounds. For instance, after 16-weeks at 20 °C, the maximum loss of flavan-3-ols (-70 %) was greater than those of hydroxycinnamic acids (-18 %) and dihydrochalcones (-12 %). We observed that flavan-3-ols formed adducts with sugars and other carbonyls, such as 5-(hydroxymethyl)furfural and the ascorbic acid-derived L-xylosone. Increased degradation rates correlated particularly with increased furan aldehyde levels as found in concentrates stored at elevated temperatures. These insights could be used for optimizing production, distribution, and storage of flavan-3-ol-rich apple juices and other foods and beverages.