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1.
J Environ Manage ; 293: 112925, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34289593

RESUMO

The development of membrane technology has proved vital in providing a sustainable and affordable supply of clean water to address the ever-increasing demand. Though liquid separation applications have been still dominated by polymeric membranes, porous ceramic membranes have gained a commercial foothold in microfiltration (MF) and ultrafiltration (UF) applications due to their hydrophilic nature, lower fouling, ease of cleaning, reliable performance, robust performance with harsh feeds, relative insensitivity to temperature and pH, and stable long-term flux. The enrichment of research and development on porous ceramic membranes extends its focus into advanced membrane separation technologies. The latest emerging nanofiltration (NF) and membrane distillation (MD) applications have witnessed special interests in constructing porous membrane with hydrophilic/functional/hydrophobic properties. However, NF and MD are relatively new, and many shortcomings must be addressed to compete with their polymeric counterparts. For the last three years (2018-2020), state-of-the-art literature on porous ceramic membranes has been collected and critically reviewed. This review highlights the efficiency (permeability, selectivity, and antifouling) of hydrophilic porous ceramic membranes in a wide variety of wastewater treatment applications and hydrophobic porous ceramic membranes in membrane distillation-based desalination applications. A significant focus on pores characteristics, pore sieving phenomenon, nano functionalization, and synergic effect on fouling, the hydrophilic porous ceramic membrane has been discussed. In another part of this review, the role of surface hydrophobicity, water contact angle, liquid entry pressure (LEP), thermal properties, surface micro-roughness, etc., has been discussed for different types of hydrophobic porous ceramic membranes -(a) metal-based, (b) silica-based, (c) other ceramics. Also, this review highlights the potential benefits, drawbacks, and limitations of the porous membrane in applications. Moreover, the prospects are emphasized to overcome the challenges in the field.


Assuntos
Membranas Artificiais , Purificação da Água , Cerâmica , Porosidade , Ultrafiltração
2.
J Environ Sci (China) ; 82: 57-69, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31133270

RESUMO

To improve the interfacial affinity and antifouling properties of polyphenylsulfone (PPSU) membrane, nano CuO/g-C3N4 (g-CN) sheets were synthesized via facile calcination route as one pot synthesis method. The uniformly assembled nanohybrid fillers, CuO on g-CN sheets were confirmed by using XRD, TEM, EDX and FTIR analysis. The non-solvent induced phase inversion technique was used to fabricate the nanohybrid ultrafiltration (UF) membranes by doping different concentration (0.5-1 wt.%) of nano CuO/g-C3N4 (g-CN) sheets within the PPSU matrix. The results of contact angle, atomic force microscopy, energy-dispersive X-ray spectroscopy reveal that surface structure and physico-chemical properties of nanohybrid membrane plays lead role in solute interaction and rejection compared to bare membrane, M0. Furthermore, the interfacial affinity of membrane was explored in detail via surface free energy, spreading coefficient, wetting tension and reversible work of adhesion analysis. Nanohybrid UF membrane, with 0.5% of the filler (M1) displayed remarkable permeation flux of 202, 131 L/m2/hr for pure water and protein solution, respectively while maintaining a high protein rejection (96%). Moreover, the exceptional dispersion of the nanosheets in the polymer matrix enhanced FRR (79%) and decreased the overall resistance of M1 compared to the pristine membrane (M0). Overall results suggest that the incorporation of nano sheets is a facile modification technique which improves the comprehensive membrane performance and holds a great potential to be further explored for water treatment.


Assuntos
Ultrafiltração/métodos , Purificação da Água/métodos , Cobre/química , Grafite/química , Interações Hidrofóbicas e Hidrofílicas , Membranas Artificiais , Nanocompostos/química , Nitrilas/química , Polímeros/química
3.
Conserv Biol ; 29(4): 1122-1131, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26129841

RESUMO

Numerous species have been pushed into extinction as an increasing portion of Earth's land surface has been appropriated for human enterprise. In the future, global biodiversity will be affected by both climate change and land-use change, the latter of which is currently the primary driver of species extinctions. How societies address climate change will critically affect biodiversity because climate-change mitigation policies will reduce direct climate-change impacts; however, these policies will influence land-use decisions, which could have negative impacts on habitat for a substantial number of species. We assessed the potential impact future climate policy could have on the loss of habitable area in biodiversity hotspots due to associated land-use changes. We estimated past extinctions from historical land-use changes (1500-2005) based on the global gridded land-use data used for the Intergovernmental Panel on Climate Change Fifth Assessment Report and habitat extent and species data for each hotspot. We then estimated potential extinctions due to future land-use changes under alternative climate-change scenarios (2005-2100). Future land-use changes are projected to reduce natural vegetative cover by 26-58% in the hotspots. As a consequence, the number of additional species extinctions, relative to those already incurred between 1500 and 2005, due to land-use change by 2100 across all hotspots ranged from about 220 to 21000 (0.2% to 16%), depending on the climate-change mitigation scenario and biological factors such as the slope of the species-area relationship and the contribution of wood harvest to extinctions. These estimates of potential future extinctions were driven by land-use change only and likely would have been higher if the direct effects of climate change had been considered. Future extinctions could potentially be reduced by incorporating habitat preservation into scenario development to reduce projected future land-use changes in hotspots or by lessening the impact of future land-use activities on biodiversity within hotspots.


La Futura Pérdida de Hábitat y Extinciones Causados por el Cambio en el Uso de Suelo en los Puntos Clave de Biodiversidad bajo Cuatro Escenarios de Mitigación de Cambio Climático Resumen Se ha llevado a numerosas especies a la extinción conforme una porción creciente de la superficie terrestre ha sido adueñada por actividades humanas. En el futuro, la biodiversidad global se verá afectada tanto por el cambio climático como por el cambio en el uso de suelo, de los cuales el último es actualmente el principal conductor de la extinción de especies. La manera en que las sociedades aborden el cambio climático afectará críticamente a la biodiversidad ya que las políticas de mitigación de cambio climático reducirán directamente los impactos del cambio climático; sin embargo, estas políticas influenciarán las decisiones de uso de suelo, lo que podría tener impactos negativos sobre el hábitat de numerosas especies. Evaluamos el impacto potencial que podrían tener las futuras políticas de clima sobre la pérdida del área habitable en los puntos clave de biodiversidad debido al cambio asociado en el uso de suelo. Estimamos las extinciones pasadas a partir de cambios históricos en el uso de suelo (1500 - 2005) con base en la extensión del hábitat, los datos de especies para cada punto clave, y la cuadrícula global de datos sobre uso de suelo, la cual fue utilizada para el Reporte de la Quinta Evaluación del Panel Intergubernamental sobre Cambio Climático. Después estimamos las extinciones potenciales causadas por futuros cambios en el uso de suelo bajo escenarios alternativos de cambio climático (2005 - 2100). El número de extinciones de especies adicionales, en relación con aquellas ya provocadas entre 1500 y 2005, causadas por el cambio en el uso de suelo para 2100 en todos los puntos clave, varió aproximadamente de 220 a 21, 000 (0.2% a 16%), dependiendo del escenario de mitigación de cambio climático y factores biológicos, como la pendiente de la relación especies-área y la contribución de la tala a las extinciones. Estas estimaciones de las extinciones potenciales en el futuro fueron causadas solamente por el cambio en el uso de suelo y probablemente habrían sido más altas si se hubiesen considerado los efectos directos del cambio climático. Las extinciones futuras podrían reducirse potencialmente al incorporar la preservación del hábitat al desarrollo del escenario para reducir los futuros cambios en el uso de suelo en los puntos clave o al disminuir el impacto de las futuras actividades de uso de suelo sobre la biodiversidad dentro de los puntos clave.


Assuntos
Biodiversidade , Mudança Climática , Conservação dos Recursos Naturais , Ecossistema , Extinção Biológica , Animais , Invertebrados , Plantas , Vertebrados
4.
Laryngoscope ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38775163

RESUMO

OBJECTIVE: To evaluate the efficacy of distal esophageal mean nocturnal baseline impedance (MNBI), a general marker of esophageal mucosal barrier integrity, in predicting laryngopharyngeal reflux (LPR) and symptomatic response to acid reflux therapy. METHODS: This retrospective study analyzed 173 patients who presented with symptoms of laryngopharyngeal reflux and underwent 24-h multichannel intraluminal impedance-pH (MII-pH) testing. Mean nocturnal baseline impedance values were calculated and assessed for their association and ability to predict LPR symptoms, MII-pH results, treatment response, and other markers of LPR. RESULTS: Notably, 153 of the 173 patients were tested off acid suppression medication and included in statistical analysis. Based on the MII-pH probe data, 108 (71%) patients had LPR, 8 (5%) had gastroesophageal reflux disease (GERD), and 37 (24%) were without pathologic reflux. Distal esophageal MNBI of LPR patients was significantly lower in LPR patients than patients with negative studies (1332 ± 94.8 vs. 2158 ± 173.5, p = 0.001). Among 118 patients who trialed antireflux therapy, a distal esophageal MNBI cutoff value of <1580 Ω was an independent predictor of treatment response (OR = 4.148 [1.877-9.189]). This value better predicted improvement with antireflux therapy for LPR than other objective MII-pH probe data, which were not independent predictors of treatment response. CONCLUSION: Distal esophageal MNBI values may have value in the diagnosis of LPR and potentially predict medication responsiveness in LPR patients. LEVEL OF EVIDENCE: 3 Laryngoscope, 2024.

5.
Environ Technol ; : 1-13, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37368861

RESUMO

In this work, a dual-pronged approach- (i) novel thin-film nanocomposite polyether sulfone (PES) membrane with MIL-101 (Fe) and (ii) 3D printed spacers were explored to enhance water recovery by forward osmosis. The concentration of PES, pore former, draw solution, and MIL-101(Fe) was optimised for maximum pure water flux (PWF) and minimum specific reverse solute flux (SRSF). The best membrane exhibited a PWF of 7.52 Lm-2 h-1 and an SRSF of 0.33 ± 0.03 gL-1 using 1.5 M NaCl and DI water feed. The M22 membrane with the diamond-type spacer demonstrated a PWF of 2.53 Lm-2 h-1 and SRSF of 0.75 gL-1 for emulsified oily wastewater feed. The novel spacer design imparted significant turbulence to the feed flow and a lower foulant resistance of 1.3 m-1 as compared to the ladder type (1.5 m-1) or commercial spacer (1.7 m-1). This arrangement could recover 19% pure water within 12 h of operation (98% oil rejection) with a ∼ 94% flux recovery after hydraulic wash.

6.
Membranes (Basel) ; 13(2)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36837695

RESUMO

In this work, inkjet printing technology was used to print a thin layer of a hydrophilic solution containing polydopamine as a binder and polyethyleneimine as a strong hydrophilic agent on a commercial hydrophobic membrane to produce a Janus membrane for membrane distillation. The pristine and modified membranes were tested in a direct-contact membrane distillation system with mineral oil-containing feedwater. The results revealed that an integrated and homogenous hydrophilic layer was printed on the membrane with small intrusions in the pores. The membrane, which contained three layers of inkjet-printed hydrophilic layers, showed a high underwater oil contact angle and a low in-air water contact angle. One-layer inkjet printing was not robust enough, but the triple-layer coated modified membrane maintained its anti-oil fouling performance even for a feed solution containing 70 g/L NaCl and 0.01 v/v% mineral oil concentration with a flux of around 20 L/m2h. This study implies the high potential of the inkjet printing technique as a facile surface modification strategy to improve membrane performance.

7.
Membranes (Basel) ; 13(5)2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37233547

RESUMO

Thin-film nanocomposite (TFN) membranes are the third-generation membranes being explored for nanofiltration applications. Incorporating nanofillers in the dense selective polyamide (PA) layer improves the permeability-selectivity trade-off. The mesoporous cellular foam composite Zn-PDA-MCF-5 was used as a hydrophilic filler in this study to prepare TFN membranes. Incorporating the nanomaterial onto the TFN-2 membrane resulted in a decrease in the water contact angle and suppression of the membrane surface roughness. The pure water permeability of 6.40 LMH bar-1 at the optimal loading ratio of 0.25 wt.% obtained was higher than the TFN-0 (4.20 LMH bar-1). The optimal TFN-2 demonstrated a high rejection of small-sized organics (>95% rejection for 2,4-dichlorophenol over five cycles) and salts-Na2SO4 (≈95%) > MgCl2 (≈88%) > NaCl (86%) through size sieving and Donnan exclusion mechanisms. Furthermore, the flux recovery ratio for TFN-2 increased from 78.9 to 94.2% when challenged with a model protein foulant (bovine serum albumin), indicating improved anti-fouling abilities. Overall, these findings provided a concrete step forward in fabricating TFN membranes that are highly suitable for wastewater treatment and desalination applications.

8.
Membranes (Basel) ; 13(9)2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37755226

RESUMO

This study presented a detailed investigation into the performance of a plate-frame water gap membrane distillation (WGMD) system for the desalination of untreated real seawater. One approach to improving the performance of WGMD is through the proper selection of cooling plate material, which plays a vital role in enhancing the gap vapor condensation process. Hence, the influence of different cooling plate materials was examined and discussed. Furthermore, two different hydrophobic micro-porous polymeric membranes of similar mean pore sizes were utilized in the study. The influence of key operating parameters, including the feed water temperature and flow rate, was examined against the system vapor flux and gained output ratio (GOR). In addition, the used membranes were characterized by means of different techniques in terms of surface morphology, liquid entry pressure, water contact angle, pore size distribution, and porosity. Findings revealed that, at all conditions, the PTFE membrane exhibits superior vapor flux and energy efficiency (GOR), with 9.36% to 14.36% higher flux at a 0.6 to 1.2 L/min feed flow rate when compared to the PVDF membrane. The copper plate, which has the highest thermal conductivity, attained the highest vapor flux, while the acrylic plate, which has an extra-low thermal conductivity, recorded the lowest vapor flux. The increasing order of GOR values for different cooling plates is acrylic < HDPE < copper < aluminum < brass < stainless steel. Results also indicated that increasing the feed temperature increases the vapor flux almost exponentially to a maximum flux value of 30.36 kg/m2hr. The system GOR also improves in a decreasing pattern to a maximum value of 0.4049. Moreover, a long-term test showed that the PTFE membrane, which exhibits superior hydrophobicity, registered better salt rejection stability. The use of copper as a cooling plate material for better system performance is recommended, while cooling plate materials with very low thermal conductivities, such as a low thermally conducting polymer, are discouraged.

9.
Scand J Child Adolesc Psychiatr Psychol ; 10(1): 163-174, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36687263

RESUMO

Background: Wolfram Syndrome is a rare genetic disorder usually resulting from pathogenic variation in the WFS1 gene, which leads to an exaggerated endoplasmic reticulum (ER) stress response. The disorder is typically characterized by diabetes insipidus, diabetes mellitus, optic nerve atrophy, hearing loss, and neurodegenerative features. Existing literature suggests it may also have psychiatric manifestations. Objective: To examine lifetime psychiatric diagnoses and medication history in Wolfram Syndrome. Method: Child, adolescent, and young adult Wolfram Syndrome participants (n=39) were assessed by a child & adolescent psychiatrist to determine best estimate DSM-5 lifetime psychiatric diagnoses as well as psychoactive medication history. In addition, the Child & Adolescent Symptom Inventory-5 (CASI-5) Parent Checklist was used to determine likely psychiatric diagnoses based on symptom counts in Wolfram Syndrome patients (n=33), type 1 diabetes (n=15), and healthy comparison (n=18) groups. Results: Study participants with Wolfram Syndrome had high lifetime rates of anxiety disorders (77%). Also, 31% had an obsessive-compulsive spectrum disorder, 33% had a mood disorder, 31% had a neurodevelopmental or disruptive behavior disorder, and 31% had a sleep-wake disorder. More than half of Wolfram Syndrome participants had taken at least one psychoactive medication, and one third had taken at least one selective serotonin reuptake inhibitor (SSRI). Some individuals reported poor response to sertraline but better response after switching to another SSRI (fluoxetine or citalopram). In general, people with Wolfram Syndrome often reported benefit from psychotherapy and/or commonly used psychoactive medications appropriate for their psychiatric diagnoses. Conclusions: Wolfram Syndrome may be associated with elevated risk for anxiety and obsessive-compulsive spectrum disorders, which seem generally responsive to usual treatments for these disorders.

10.
Polymers (Basel) ; 14(24)2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36559716

RESUMO

Membrane distillation (MD) is an emerging technology for water recovery from hypersaline wastewater. Membrane scaling and wetting are the drawbacks that prevent the widespread implementation of the MD process. In this study, coaxially electrospun polyvinylidene fluoride-co-hexafluoropropylene (PVDF-co-HFP) nanofibrous membranes were fabricated with re-entrant architecture and enhanced hydrophobicity/omniphobicity. The multiscale roughness was constructed by incorporating Al2O3 nanoparticles and 1H, 1H, 2H, 2H Perfluorodecyltriethoxysilane in the sheath solution. High resolution transmission electron microscopy (HR-TEM) could confirm the formation of the core-sheath nanofibrous membranes, which exhibited a water contact angle of ~142.5° and enhanced surface roughness. The membrane displayed a stable vapor flux of 12 L.m−2.h−1 (LMH) for a 7.0 wt.% NaCl feed solution and no loss in permeate quality or quantity. Long-term water recovery from 10.5 wt.% NaCl feed solution was determined to be 8−10 LMH with >99.9% NaCl rejection for up to 5 cycles of operation (60 h). The membranes exhibited excellent resistance to wetting even above the critical micelle concentration (CMC) for surfactants in the order sodium dodecyl sulphate (SDS) (16 mM) > cetyltrimethylammonium bromide (CTAB) (1.5 mM) > Tween 80 (0.10 mM). The presence of salts further deteriorated membrane performance for SDS (12 mM) and Tween-80 (0.05 mM). These coaxial electrospun nanofibrous membranes are robust and can be explored for long-term applications.

11.
JMIR Diabetes ; 6(2): e27027, 2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34081017

RESUMO

Type 1 diabetes (T1D) is one of the most common chronic childhood diseases, and its prevalence is rapidly increasing. The management of glucose in T1D is challenging, as youth must consider a myriad of factors when making diabetes care decisions. This task often leads to significant hyperglycemia, hypoglycemia, and glucose variability throughout the day, which have been associated with short- and long-term medical complications. At present, most of what is known about each of these complications and the health behaviors that may lead to them have been uncovered in the clinical setting or in laboratory-based research. However, the tools often used in these settings are limited in their ability to capture the dynamic behaviors, feelings, and physiological changes associated with T1D that fluctuate from moment to moment throughout the day. A better understanding of T1D in daily life could potentially aid in the development of interventions to improve diabetes care and mitigate the negative medical consequences associated with it. Therefore, there is a need to measure repeated, real-time, and real-world features of this disease in youth. This approach is known as ecological momentary assessment (EMA), and it has considerable advantages to in-lab research. Thus, this viewpoint aims to describe EMA tools that have been used to collect data in the daily lives of youth with T1D and discuss studies that explored the nuances of T1D in daily life using these methods. This viewpoint focuses on the following EMA methods: continuous glucose monitoring, actigraphy, ambulatory blood pressure monitoring, personal digital assistants, smartphones, and phone-based systems. The viewpoint also discusses the benefits of using EMA methods to collect important data that might not otherwise be collected in the laboratory and the limitations of each tool, future directions of the field, and possible clinical implications for their use.

12.
Environ Sci Pollut Res Int ; 28(10): 11915-11927, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32072412

RESUMO

Effluents from food, fermentation, and sugar industries contain a large quantity of glucose which has to be removed to limit the chemical oxygen demand (COD) of the water discharged. This work proposes novel thin-film nanocomposite (TFN) membranes incorporated with MgFe2O4 and ZnFe2O4 nanoparticles to address this concern. The nanoparticles synthesized by the sol-gel method was extensively characterized and then incorporated into the active polyamide layer of the thin-film composite polysulfone membranes. The change in membrane morphology, wettability, chemical structure, and mechanical strength with the incorporation of nanoparticles was studied in detail. Membranes with 0.005 wt.% MgFe2O4 nanoparticle exhibited highest glucose rejection (96.52 ± 2.35%) at 10 bar, 25 °C, and sufficiently high pure water flux (50.54 ± 1.92 L/m2h). This membrane also displayed 69.1 ± 5.12% salt rejection when challenged with 2000 ppm synthetic NaCl solution.


Assuntos
Nanocompostos , Purificação da Água , Compostos Férricos , Polímeros , Sulfonas
13.
RSC Adv ; 9(71): 41462-41474, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-35541587

RESUMO

In this research work, novel perfluorooctanoic acid-modified melamine (PFOM) was synthesized as a hydrophobic filler using a facile one-pot synthesis. PFOM incorporating polyvinylidene fluoride (PVDF) solution was cast on a cellulose sheet to prepare a dual-layered membrane employing the phase-inversion technique for direct contact membrane distillation (DCMD) application. The influence of PFOM to tailor the dual-layered membrane performance was then investigated. The long perfluoro chain in PFOM hydrophobic fillers increased the surface roughness of the membranes due to its random overlapping with PVDF backbone, and these membranes exhibited a higher water contact angle value. The increase in pore size and membrane porosity did not significantly influence the liquid entry pressure of water (LEPw). The microporous membranes displayed good mechanical strength for use in the test setup. Pure water permeation was the highest (6.9 kg m-2 h-1) for membrane (M1) with 1 wt% of PFOM when tested with a simulated sea-water solution (3.5% w/v NaCl) in the direct contact distillation mode. These membranes also achieved the theoretical salt-rejection of 99.9%, thus confirming the potential of these membranes to be investigated for large scale membrane distillation (MD) applications like desalination of seawater.

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