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ACS Omega Jun 2024Solution blowing is a rapidly developing technology for the rapid and large-scale preparation of nanofibers, driven by its advantages, such as wide adaptability to raw...
Solution blowing is a rapidly developing technology for the rapid and large-scale preparation of nanofibers, driven by its advantages, such as wide adaptability to raw materials, simple and safe operation, and ease of scalable production. Most of the research related to solution blowing mainly focuses on the fiber spinning and forming principle, fiber structure and properties, and the development of new materials. Limited studies have focused on the airflow field and fiber motion in solution blowing. In this paper, nine nozzles for solution blowing with varying geometrical parameters were designed by adjusting the outer nozzle diameter, inner nozzle outstretched distance, and inner nozzle diameter. The centerline airflow velocity, turbulence intensity, and velocity distribution of the solution blowing were analyzed using the numerical simulation method. The results showed that the outer nozzle diameter had the greatest influence on the air velocity and turbulence intensity. The airflow velocity increased and the turbulence intensity decreased with the increase of the outer nozzle diameter. The inner nozzle outstretched distance only affected the airflow convergence point and had less effect on the airflow velocity and turbulence intensity. The captured trajectory of the polymer jet initially shows a straight or slightly curved development that eventually diverges from the airflow field. With an increasing distance, dispersed fibers exhibit instability, including loop formation, bonding, and separation. The experimental observation of fiber morphology in the solution-blowing web further verified the instability during the fiber movement.
PubMed: 38947848
DOI: 10.1021/acsomega.3c09876 -
ACS Omega Jun 2024The automotive industry is always seeking novel solutions to improve the durability and the performance of textile materials used in vehicles. Indeed, especially after...
The automotive industry is always seeking novel solutions to improve the durability and the performance of textile materials used in vehicles. Indeed, especially after the coronavirus pandemic, antibacterial treatments have gained interest for their potential of ensuring cleanliness and safety toward microbial contamination within vehicles. This study gives a panoramic view of the durability of antibacterial treatments applied on textile materials in the automotive industry, focusing on their performance after experiencing accelerated aging processes. Two different textile materials, a fabric and a synthetic leather, both treated with antibacterial agents, were tested according to ISO 22196 and ISO 20743 standards, respectively, using two model microorganisms, and . The impact of mechanical, thermal, and solar aging on the antibacterial properties has been evaluated. In addition, scanning electron microscope (SEM) analysis was performed to investigate the surface morphology of the materials before and after aging. Furthermore, contact angle measurements were conducted. The results suggest that neither mechanical nor thermal aging processes determined diminished antibacterial action. It was determined, instead, that the most damaging stressor for both textile materials was UV aging, causing severe surface alterations and a reduction in antibacterial activity.
PubMed: 38947847
DOI: 10.1021/acsomega.4c01272 -
ACS Omega Jun 2024The densities of eutectic (LiF)-BeF and mixtures of this salt (FLiBe) with LaF were measured by dilatometry and by neutron attenuation from 673 K to 1,073 K. Because LaF...
The densities of eutectic (LiF)-BeF and mixtures of this salt (FLiBe) with LaF were measured by dilatometry and by neutron attenuation from 673 K to 1,073 K. Because LaF has a limited solubility in FLiBe, it was necessary to determine the amount of LaF in solution before the density could be determined. The FLiBe density determination was favorably benchmarked against the literature data. A simple comparison was not available for the LaF-FLiBe mixtures, so extrapolation of published data was necessary based on analysis using the Molten Salt Thermal Properties Database-Thermochemistry, or MSTDB-TC, developed by the US Department of Energy. Solubilities for LaF in FLiBe ranged from 1 to 4 mol % over 673 to 1,073 K. The salt system was heated and cooled over 24 h to evaluate potential changes in composition and hysteresis during the measurement. Changes in the meniscus were observed, and these were included in the correction for density determinations. Salt surface tension may have led to supersaturation of LaF in the salt because the solubility curve was nonlinear with respect to the inverse temperature, as would be expected for an ideal system. Surface tension measurements are currently underway to test this hypothesis.
PubMed: 38947831
DOI: 10.1021/acsomega.4c01446 -
ACS Omega Jun 2024Toluene is a common and significant volatile organic compound (VOC). Although it finds extensive application in various industrial processes (chemical manufacturing,... (Review)
Review
Toluene is a common and significant volatile organic compound (VOC). Although it finds extensive application in various industrial processes (chemical manufacturing, paint and adhesive production, and as a solvent), it creates a huge environmental impact when emitted freely into the atmosphere. Two solutions were found to mitigate the emission of this pollutant: the total oxidation to CO and HO and the selective oxidation into benzaldehyde. This review discusses the two main alternatives for tackling this problem: converting the toluene into carbon dioxide by total oxidation or into benzaldehyde by selective oxidation. It presents new catalytic advances, new trends, and the advantages and disadvantages of both methods.
PubMed: 38947821
DOI: 10.1021/acsomega.4c01023 -
ACS Omega Jun 2024The durability of Pt nanoparticle catalysts is currently the most important factor limiting the widespread use of polymer electrolyte fuel cells (PEFCs). Specifically,...
The durability of Pt nanoparticle catalysts is currently the most important factor limiting the widespread use of polymer electrolyte fuel cells (PEFCs). Specifically, the Pt nanoparticles in standard carbon black-supported Pt nanoparticle (Pt/CB) catalysts repeatedly aggregate on the CB surfaces during PEFC operation, thus, reducing the performance of the cell. Therefore, PEFCs must contain large quantities of Pt to maintain sufficient service lifetimes. This is the main factor hindering the reduction of the cost of PEFCs. The present research demonstrates that ultrafine Pt particles (Pt) having diameters of approximately 0.5 nm can be formed in situ from a platinum chloride complex (PtCl ) on a carbon-based material doped with Fe and N via the dissolution and reprecipitation of Pt in the PtCl during potential cycling in a 0.1 M HClO solution. The Pt are immobilized by both Fe and N in the support material. The mass-based catalytic activity of this material during the oxygen reduction reaction is eight times higher than that of a standard Pt/CB catalyst and is maintained even after 100,000 potential step cycles (0.6 ↔ 1.0 V). The present results provide guidelines for the development of highly durable yet active membrane electrode assemblies that minimize the use of Pt.
PubMed: 38947817
DOI: 10.1021/acsomega.4c02723 -
ACS Omega Jun 2024The work is focused on the degradation, cytotoxicity, and antibacterial properties, of iron-based biomaterials with a bioactive coating layer. The foam and the compact...
The work is focused on the degradation, cytotoxicity, and antibacterial properties, of iron-based biomaterials with a bioactive coating layer. The foam and the compact iron samples were coated with a polyethylene glycol (PEG) polymer layer without and with gentamicin sulfate (PEG + Ge). The corrosion properties of coated and uncoated samples were studied using the degradation testing in Hanks' solution at 37 °C. The electrochemical and static immersion corrosion tests revealed that the PEG-coated samples corroded faster than samples with the bioactive PEG + Ge coating and uncoated samples. The foam samples corroded faster compared with the compact samples. To determine the cytotoxicity, cell viability was monitored in the presence of porous foam and compact iron samples. The antibacterial activity of the samples with PEG and PEG + Ge against CCM 3954 and CCM 4223 strains was also tested. Tested PEG + Ge samples showed significant antibacterial activity against both bacterial strains. Therefore, the biodegradable iron-based materials with a bioactive coating could be a suitable successor to the metal materials studied thus far as well as the materials used in the field of medicine.
PubMed: 38947814
DOI: 10.1021/acsomega.4c01002 -
ACS Omega Jun 2024In the development of edgewater-type carbonate gas reservoirs, the challenge posed by water flooding in production wells is a significant concern. This study...
In the development of edgewater-type carbonate gas reservoirs, the challenge posed by water flooding in production wells is a significant concern. This study investigates the potential of CO injection as a solution for water control. Experiments were conducted to understand the gas-water flow dynamics during CO-controlled water injection in a series-connected core. Emphasis was placed on the effects of varying the CO injection pressure on water flow and gas cumulative production rate. The mechanisms influencing water control and production efficiency across different injection pressures in multiwell production were elucidated. The results showed that the gas production rate of the core increased by 27.2% over the depletion production rate after the CO injection pressure was increased from 8 to 13 MPa. The gas production rate increases during the second development cycle from 20% to 55% after switching to CO injection, which pushes the edge water further back, slowing down side water flow in the core in the form of segmental plugs, and prolonging the time before water breakthrough. The production time and water breakthrough time for the second development cycle increased with increasing CO injection, while the degree of water flow on the core side decreased. These insights are crucial for optimizing the recovery efficiency of edgewater-type gas reservoirs and provide guidance on the application of CO injection for water control and CO sequestration in carbonate gas reservoirs.
PubMed: 38947811
DOI: 10.1021/acsomega.3c08901 -
ACS Omega Jun 2024Hybrid microgels made from starch nanoparticles (SNPs) and poly(-isopropylacrylamide) p(NIPAM) were used as promising hosts for the methylene blue (MB) dye. In this...
Hybrid microgels made from starch nanoparticles (SNPs) and poly(-isopropylacrylamide) p(NIPAM) were used as promising hosts for the methylene blue (MB) dye. In this paper, these thermoresponsive microgels were characterized by dynamic light scattering (DLS), zeta potential measurements (ZP), and scanning electron microscopy (SEM) and evaluated as carriers for skin-targeted drug delivery. The hybrid microgel-MB systems in PBS solution were also studied by UV-vis spectroscopy and DLS, revealing discernible differences in spectral intensity and absorption shifts compared to microgels devoid of MB. This underscores the successful integration of methylene blue within the SNPs--p(NIPAM) microgels, signifying their potential as efficacious drug delivery vehicles.
PubMed: 38947796
DOI: 10.1021/acsomega.4c01947 -
ACS Omega Jun 2024Vesicle hydrogels are supramolecular structures formed by the self-assembly of surfactant molecules in solution, which have great application prospects. The phase...
Vesicle hydrogels are supramolecular structures formed by the self-assembly of surfactant molecules in solution, which have great application prospects. The phase behavior of perfluorononanoic acid (CFCOOH) and an amphoteric hydrocarbon surfactant, tetradecyl dimethylaminoxide (CDMAO), in an aqueous solution has been studied. By changing the mixing ratio and concentration of CFCOOH and CDMAO, the phase diagram of the system was drawn, and interestingly, a hydrogel composed of polyhedral and spherical vesicles was successfully constructed. The formation mechanism of the polyhedral and spherical vesicle hydrogel was studied by differential scanning calorimetry (DSC), small-angle X-ray diffraction (XRD), wide-angle X-ray scattering (WAXS), and H nuclear magnetic resonance (H NMR) measurements, and the rheological properties and influencing factors of the hydrogel were systematically investigated. The formation of the vesicle hydrogels in this system was considered to be caused by the "cocrystallization" of two surfactant molecular chains.
PubMed: 38947782
DOI: 10.1021/acsomega.4c02696 -
ACS Omega Jun 2024Imbalance of potassium-ion levels in the body can lead to physiological dysfunctions, which can adversely impact cardiovascular, neurological, and ocular health. Thus,...
Imbalance of potassium-ion levels in the body can lead to physiological dysfunctions, which can adversely impact cardiovascular, neurological, and ocular health. Thus, quantitative measurement of potassium ions in a biological system is crucial for personal health monitoring. Nanomaterials can be used to aid in disease diagnosis and monitoring therapies. Optical detection technologies along with molecular probes emitting within the near-infrared (NIR) spectral range are advantageous for biological measurements due to minimal interference from light scattering and autofluorescence within this spectral window. Herein, we report the development of NIR fluorescent nanosensors, which can quantitatively detect potassium ions under biologically relevant conditions. The optical nanosensors were developed by using photoluminescent single-walled carbon nanotubes (SWCNTs) encapsulated in polymers that contain potassium chelating moieties. The nanosensors, polystyrene sulfonate [PSS-SWCNTs, nanosensor 1 (NS1)] or polystyrene--polystyrene sulfonate [PS--PSS-SWCNTs, nanosensor 2 (NS2)], exhibited dose-dependent optical responses to potassium ion level. The nanosensors demonstrated their biocompatibility via the evaluation of cellular viability, proliferation assays, and expression of cytokeratin 12 in corneal epithelial cells (CEpiCs). Interestingly, the nanosensors' optical characteristics and their responses toward CEpiCs were influenced by encapsulating polymers. NS2 exhibited a 10 times higher fluorescence intensity along with a higher signal-to-noise ratio as compared to NS1. NS2 showed an optical response to potassium ion level in solution within 5 min of addition and a limit of detection of 0.39 mM. Thus, NS2 was used for detailed investigations including potassium ion level detection in serum. NS2 showed a consistent response to potassium ions at the lower millimolar range in serum. These results on optical sensing along with biocompatibility show a great potential for nanotube sensors in biomedical research.
PubMed: 38947780
DOI: 10.1021/acsomega.4c01867