The Fenton membrane is effective in removing organic pollutants from wastewater through the synergy of Fenton catalysis and membrane separation. However, the preparation of a Fenton membrane with ...excellent self-cleaning performance, catalytic ability, and stability remains a key research direction. Herein, a polyethersulfone (PES)/Fe3S4@NiO membrane was obtained via a non-solvent phase inversion method. The intercalation of photo-Fenton catalytic Fe3S4@NiO into the PES membrane can not only enhance the hydrophilicity but also endow the membrane with photo-Fenton catalytic activity. The separation efficiency of the obtained membrane for multiple oil-in-water emulsions exceeded 98.8%. In addition, the membrane presented excellent self-cleaning performance and stability, the separation efficiency remained high and stable even after 10 cycles of oil-in-water emulsions. Meanwhile, the effective degradation of several organic dyes under visible light was simulated; results showed that the membrane can achieve nearly 100% degradation of methylene blue in 9 min as well as rhodamine B and methyl orange in 3 min, and this membrane maintained high degradation efficiency (>98.7%) even after 5 cycles. Therefore, the results indicate that this PES/Fe3S4@NiO membrane has excellent separation performance and photo-Fenton activity, and the proposed membrane has a potential application scope for efficient emulsion separation and speedy dye degradation.
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•Multifunctional PES/Fe3S4@NiO Fenton membrane with underwater super-oleophobicity and excellent catalytic performance was successfully prepared.•Separation of insoluble oil from the oil-water emulsion.•Self-cleaning and anti-fouling properties prolong the service life of the membrane.•Photo-Fenton degradation of organic pollutants for further water purification.
ABSTRACT
Foot type has been associated with pain, injury, and altered gait mechanics. Morphological variations in foot bones due to foot type variation may impact surgical and therapeutic treatments. ...The purpose of this study was to utilize principal component analysis (PCA) to determine how morphology of the hind‐ and midfoot bones differs among foot types and sex. The calcaneus, talus, navicular, and cuboid were segmented using previously obtained computed tomography (CT) scans and converted to surface models. The CTs were sorted into four foot types—cavus, neutrally aligned, asymptomatic planus, and symptomatic planus. Morphometric shape analysis software (Geomorph) was used to perform a PCA to determine which components varied between foot types and between sexes. The calcaneus showed planus feet of both types to have calcanei that have decreased height and increased length compared to neutrally aligned feet. The talus demonstrated increased posterior mass for cavus feet compared to neutrally aligned feet. For the navicular, symptomatic planus had a more posteriorly positioned tuberosity and were wider than asymptomatic planus feet. The cuboid did not exhibit any differences between foot types. Sex differences, found only at the talus and navicular, were subtle. PCA is an objective technique that helped elucidate differences in bone morphology between foot types and sex without needing to determine the features of interest before comparing groups. Understanding these variations can help inform diagnosis of foot pathologies and surgical protocols as well as improve computer models of the foot. Published 2018. This article is a U.S. Government work and is in the public domain in the USA. J Orthop Res 9999:1–16, 2019.
The purpose of this study was to utilize principal component analysis to determine how morphology of the hind‐ and midfoot bones differs due to foot types or sex. Computed tomography scans of cavus, neutrally aligned, asymptomatic planus, and symptomatic planus feet were used for analysis. Morphometric shape analysis elucidated differences in bone morphology among foot types for the calcaneus, talus, and navicular as well as sex‐based differences for the talus. No differences were seen for the cuboid.
PES–TiO
2 composite membranes were prepared via phase inversion by dispersing TiO
2 nanopaticles in PES casting solutions. The crystal structure, thermal stability, morphology, hydrophilicity, ...permeation performance, and mechanical properties of the composite membranes were characterized in detail. XRD, DSC and TGA results showed that the interaction existed between TiO
2 nanopaticles and PES and the thermal stability of the composite membrane had been improved by the addition of TiO
2 nanopaticles. As shown in the SEM images, the composite membrane had a top surface with high porosity at low loading amount of TiO
2, which was caused by the mass transfer acceleration in exposure time due to the addition of TiO
2 nanopaticles. At high loading amount of TiO
2, the skinlayer became much looser for a significant aggregation of TiO
2 nanopaticles, which could be observed in the composite membranes. EDX analysis also revealed that the nanoparticles distributed in membrane more uniformly at low loading amount. Dynamic contact angles indicated that the hydrophilicity of the composite membranes was enhanced by the addition of TiO
2 nanopaticles. The permeation properties of the composite membranes were significantly superior to the pure PES membrane and the mean pore size also increased with the addition amount of TiO
2 nanopaticles increased. When the TiO
2 content was 4%, the flux reached the maximum at 3711
L
m
−2
h
−1, about 29.3% higher than that of the pure PES membrane. Mechanical test also revealed that the mechanical strength of composite membranes enhanced as the addition of TiO
2 nanopaticles.
Photoelectron spectroscopy (PES) investigation of two widely used herbicide compounds MCPA and 2,4-D is reported. The GW calculations are shown to offer a good description of their electronic ...structure. There is excellent agreement between the experimental and theoretical energies of the HOMO states of 2,4-D and MCPA, which are at 8.7 eV and 8.5 eV binding energy, respectively. The low energy tail of the HOMO state extends to about 8 eV. The good agreement between the UPS (ultraviolet photoelectron spectroscopy) spectra and the simulation validates the proposed conformer. The presented gas phase data will help researchers to analyze data from liquid and diluted samples of these herbicide molecules and perform additional theoretical modelling.
•The UPS spectra of two widespread herbicides MCPA and 2,4-dichlorophenoxyacetic acid have been obtained and analyzed.•A side-by-side comparison of the geometric and electronic structures is presented.•There is excellent agreement between the experimental and theoretical energies of the HOMO states of 2,4-D and MCPA, which are at 8.7 eV and 8.5 eV binding energy, respectively.
•Pyrolysis behavior of ultrafiltration membranes were studied using TG-FTIR-GC–MS.•The elemental, proximate, and compositional analyses of membranes were measured.•Pyrolysis kinetics of membranes ...were studied using model-free models.•TGA and DTG curves were simulated using DAEM and IPR models.•Sulfur dioxide, benzene, phenol, and diphenyl ether were the major compounds in GC–MS.
This is the first research to be concerned with end-life ultrafiltration polymer nanocomposite membranes and their valorization into high added-value products using the pyrolysis treatment. Polysulfone membrane (PES) as a commercial product and their nanocomposites (CNTs/PES and graphene/PES) were used as a feedstock in the present research. The experiments started with fabrication of membranes loaded with 0.04 wt% of CNTs and graphene (GNs). The elemental analysis and proximate analysis of the fabricated membranes were studied. Subsequently, thermogravimetric coupled with Fourier-transform infrared spectroscopy (TG-FTIR) system was used to study the thermal and chemical decomposition of the membranes at different heating rates (5-30˚C/min). The volatile products released from the pyrolysis process of the membranes were analyzed using TG coupled with gas chromatography–mass spectrometry (GC–MS) unit. Finally, pyrolysis kinetic parameters of PES membrane and its nanocomposites were studied using model-free models. Also, thermogravimetry and differential thermal gravimetry (TG/DTG) experimental data were simulated using the distributed activation energy model and the independent parallel reactions kinetic model with high predictability. The results showed that sulfur dioxide, benzene, phenol, and diphenyl ether compounds represented the main compounds in the released volatile components with high total abundance, especially at high heating rate and estimated at 85% (PES), 94% (CNTs/PES), and 99% (GNs/PES). Meanwhile. the kinetics analysis showed that the whole activation energies decreased significantly in case of nanocomposites by this trend 206.4 kJ/mol (PES), 187.8 kJ/mol (CNTs/PES), and 139.30 kJ/mol (GNs/PES), what indicates that CNTs and GNs act as self-catalysts and end-life polymer membranes can be used as a new source for renewable energy.
•CNTs/PES and Graphene/PES membranes were prepared using doctor-blade.•The pore topology of the synthesized membranes was observed using SEM.•Mechanical properties of the membranes were measured.•A ...nonlinear uniaxial model was built to simulate the mechanical performance.•The mechanical properties were reduced up to 26% for CNTs and 57% for GA.•The model is valid for deducing the uniaxial curves with deviation (0.164-0.715%).
Polyethersulfone (PES) nanocomposite membranes are some of the emerging ultrafiltration technologies that have promising applications in gas separation and wastewater treatment due to their unique microporous structure and cheapness. However, the effect of nanofiller additives on their mechanical and viscoelastic properties is still missing and these fundamentals should be known to designers and manufacturers for potential upscaling. In this context, this research aims to study the uniaxial mechanical behaviors of PES membranes and their nanocomposites (CNTs/PES and Graphene/PES), and then to model their mechanical characteristics based on the results of mechanical experiments. In order to achieve that, four batches from CNTs/PES and Graphene/PES nanocomposite membranes with different concentrations of nanofillers (0.01-0.04 wt.%) were prepared using a solution casting method and a tape casting process. Also, another neat PES batch was prepared for comparison. The pore topology of the synthesized membranes was observed using SEM. Afterwards, the mechanical tensile specimens were cut from the synthesized membranes and tested according to standard ASTM 638M-3 using a uniaxial universal testing machine. Finally, a nonlinear uniaxial stress-strain model was built to simulate the mechanical performance of the fabricated membranes using the generalized Maxwell model. The results showed that the mechanical properties of the membranes were reduced significantly by additives (up to 26% for CNTs and 57% for GA compared with neat batch) because of the changes in the pore topology (orientation, size, and distribution) of the prepared membranes,whereas the modeling results showed that the constitutive model is valid for deducing the uniaxial stress-strain curves of PES membrane and its nanocomposites membranes with a high predictability and average deviation estimated at 0.715% (PES), 0.302% for CNTs/PES and 0.164% for GA/PES membranes.
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Introduction
Subtalar arthroereisis has been increasingly accepted as a solution to manage symptomatic pes planus. However, despite the recent developments related to arthroereisis, no other ...published literature has aimed to review the outcomes in paediatric patients since 2010. This systematic review and meta-analysis, therefore, aims to evaluate the current outcomes of subtalar arthroereisis in the treatment of symptomatic pes planus among the paediatric population.
Materials and methods
The review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. All studies reported on the clinical outcomes of subtalar arthroereisis in children aged 21 or younger were included.
Results
A total of 17 publications were included, with 1536 feet. The average duration of follow-up of the studies included in the review is 43.52 months. The studies consistently reported improvement in the radiological outcomes, approximating that of a normal population. Subtalar arthroereisis has shown to restore the collapsed medial longitudinal arch, supported by the decrease in Meary’s angle to 5.267° (95% CI: 4.695°–5.839°, normal: 0°–10.0°) post-operatively and an increased calcaneal pitch of 15.70° (95% CI: 15.41°–15.99°, normal 18.0°–20.0°). Deformities associated with pes planus such as heel valgus was also significantly reduced, evident by the post-operative lateral talocalcaneal angle of 27.19° (95% CI: 26.44°–27.93°, normal: 25.0°–45.0°) and a post-operative Kite’s angle of 18.13° (95% CI: 17.73°–18.52°, normal: 15.0°–30.0°). Subjectively, subtalar arthroereisis has generally resulted in an improvement in the grading of outcomes postoperatively from the patient’s point of view.
Conclusions
Subtalar arthroereisis could serve as a procedure to correct radiological abnormalities, as well as relieve pain in selected patients with symptomatic pes planus.
The objective of this study is to examine the implementation of a combined scheme involving payment environment services (PES) and non-payment environment services (non-PES) in the management of the ...Cidanau River Basin. This study used exploratory research to analyse the structure and mechanism of PES and non-PES schemes for the governance system. The Cidanau Watershed governance is a pioneer in sustainable integrated water resources management in Indonesia and has persisted until the present time. The governance of the Cidanau Watershed is dynamic, resilient, and evolving in response to various changes in social and ecological systems. A bridging organisation like the Cidanau Watershed Communication Forum (Ind.: Forum Komunikasi DAS Cidanau – FKDC) requires legal standing to be visible and gain the trust of the public, especially when implementing a PES approach like the Cidanau River Basin, where service buyers utilise non-direct payment mechanisms. The challenging aspect of developing a PES scheme is empowering knowledge regarding the importance of soil and water preservation among upstream communities, particularly in developing countries like Indonesia, where upstream communities are predominantly composed of low-income farmers whose livelihoods depend on nature. The non-PES scheme represents the government’s mandatory responsibility, whereas the PES scheme presents public participation in active collaboration through the FKDC as an ad hoc institution. A combination of the non-PES and PES scheme approach can serve as a model and reference for similar river basin governance frameworks. Further research is needed regarding social networks and institutional development of sustainable watershed governance in the Cidanau River Basin.
Increasing acceptance of payments for ecosystem services (PES) programs as environmental policy alternatives suggests a clear need for research on PES implementation, both to validate theoretical ...frameworks and improve approaches for existing and future programs. We provide a history of the 10-year old Conservador das Águas program in Extrema, a city in Minas Gerais located within the Atlantic Forest of Brazil. To date, the program has coordinated restoration activities that have increased native forest cover in 60% in targeted sub-watershed through contracts with 53 landowners, and has established long-term collaborations among government agencies, civil society, and landowners. Evaluation of the institutional elements of the program using an institutional framework reveals lessons that are relevant for future projects. We find that national legislation and local government organizations have played key roles in enabling and maintaining program activities. Further, strategic decisions by program staff, including targeting important regions and actors within the municipality, the use of Forest Code mandates as an incentive for participation, and use of municipal legislation to secure funding, were critical to the program's success. We use an institutional framework to provide a review of the program, including its legal context, actors, and financial instruments, for those engaged in establishing and sustaining similar programs.
•An institutional analysis of the Conservador das Águas program was conducted.•The program has contributed to a 60% increase in native forest on private land.•Synergies with national legislation were key to supporting a municipal project.•Municipal capacity was key to build trust and encourage landowner participation.•Strategic work with partners and spatial targeting increased project impacts.
Polar organic chemical integrative sampler (POCIS) contains sorbent, which is typically enclosed between two polyethersulfones (PES) membranes. A significant PES uptake is reported for many ...contaminants, yet, aqueous concentration is mainly correlated with the sorbent uptake using first-order kinetics. Under high PES sorption, the first-order kinetics often provide erroneous sampling rate for the sorbent phase due to increased membrane resistance. This work evaluated the uptake of four high PES sorbing chemicals, i.e., three Cl- and CH3-substituted nitrobenzenes and one chlorinated aniline using POCIS and the potential of a single-phase PES sampler using laboratory experiments. POCIS calibration results demonstrated that both sorbent and membrane had similar affinity for the target compounds. A rapid PES sorption occurred in the earlier days (<7 days) followed by a gradual increase in the PES phase concentration (equilibrium not achieved after 60 days). Especially, the membrane was the primary sink for 3,4-dichloroaniline and 3,4-dichloronitrobenzene for up to 14 and 31 days, respectively. On the other hand, the single-phase PES sampler showed similar mass uptake as POCIS and reached equilibrium within 19 days under static condition, indicating its potential suitability in the equilibrium regime. PES-water partition coefficient of the target compounds was between 1.2 and 6.5 L/g. Finally, we present a poly-parameter linear-free energy relationship (pp-LFER) using published data to predict the PES-water partition coefficients. The pp-LFER models showed moderate predictability as indicated by R2adj values between 0.7 and 0.9 for both internal and external data set consisting of a wide range of hydrophobic and hydrophilic compounds (−0.1 ≤ logKOW ≤ 7.4). The proposed pp-LFER model can be used to screen high PES-sorbing chemicals to increase the reliability and accuracy of aqueous concentration prediction from POCIS sampling and to select the most appropriate sampling approach for new compounds.
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•Significant PES sorption in POCIS affects Rs calculation using first-order models.•Comparable mass uptake by single-phase PES and POCIS for substituted chlorobenzenes•PES-water partition can be calculated using developed pp-LFER model.•Model shows PES sampler can be used for both hydrophilic and hydrophobic chemicals.•Developed pp-LFER model can screen suitable compounds for PES and POCIS samplers.