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Overcoming heterocoagulation challenge in selective flotation separation between lithium cobalt oxide and lithium manganese oxide
No full textEfficient separation of mixed cathode active materials from recycled Li-ion batteries is a prerequisite for both the successful direct recycling and hydrometallurgical recycling of spent lithium-ion batteries (LIBs). In this work, separation between lithium cobalt oxide (LCO) and lithium manganese oxide (LMO) was investigated using the froth flotation method. Sodium octanohydroxamate (OHA) was employed as the collector. It was found that individual LCO materials could be selectively hydrophobized by OHA and floated by air bubbles, while LMO materials could not be floated using OHA as the collector. Unfortunately, the flotation separation of a binary mixture of LCO and LMO in DI water was poor due to the heterocoagulation between these two cathode materials. With the addition of sodium metasilicate as the dispersant, the flotation separation of the two was significantly improved. The mechanism was investigated using ζ-potential measurements, SEM analysis, and DLVO force analysis. It was found that the ζ-potentials of both LCO and LMO were slightly negatively charged at a pH of 7 to 9, resulting in the heterocoagulation between the two cathode materials. The addition of sodium metasilicate increased the magnitude of negative ζ-potential and therefore improved particle dispersion and separation efficiency. The present work demonstrated the importance of dispersants in the separation of mixed cathode materials from Li-ion batteries
Fast recovery and ultrasensitive net-graphene sensor for monitoring SF6 decomposition by-products
No full textPower industry insulator sulfur hexafluoride (SF6) has excellent dielectric properties. However, SF6 decomposes into by-products over time, making their detection essential for power device evaluation and fault prevention. Recently, 2D materials, especially carbon-based ones, have become excellent gas sensing platforms, expected to lead the next generation of sensors. Because graphitic materials and SF6 decomposition products have weak van der Waals interactions, functionalization has been the most promising way to improve surface-molecule interactions, but it also presents experimental challenges. We propose monitoring SF6 degradation with a pristine net-graphene nanosensor to address these issues. Here, density functional theory and non-equilibrium Green\u27s functions methods are used to study the interaction between net-graphene device and gas-insulated switchgear atmosphere gas (SF6, CO2, N2, H2O, and O2), as well as the decomposition products of SF6. These molecules are physisorbed on net-graphene, causing p-type doping in the device. The system\u27s conductance is modulated by molecule-net-graphene interactions, allowing target molecule detection and identification. We propose a field-effect device that can sense SO2 and H2S without cross-selectivity and with a fast recovery time. It is also resistant to O2 and H2O degradation. We found that net-graphene is a promising nanomaterial for real-time monitoring of power industry SF6 decomposition by-products
DNA gyrase inhibition by Ni(II)-Schiff base complexes via in silico molecular docking studies: Spectroscopic, DFT calculations and in vitro pharmacological assessment
Get PDFThe current world\u27s life-threatening illnesses have amplified multidrug resistance infections, bringing about immune system mayhem, thus, the quest for novel antimicrobial compounds with a broad spectrum of action. Four Ni(II) complexes, [Ni(YB)Cl]·2H2O (C1), [Ni(YB)Br]·H2O (C2), [Ni(YB)NO3]·3H2O (C3), [Ni(YB)COOCH3]·2H2O (C4) [HYB = 4-[(1E)-N-{2-[(Z)-(4-methoxybenzylidene)amino]ethyl}ethanimidoyl]benzene-1,3-diol], were synthesized. Analytical techniques like CHNS analysis, UV–Vis, FT-IR, molar conductance, XRD, 1H NMR, and TGA/DTA were utilized for characterization. The calculated EHOMO – ELUMO energy gap and global reactivity descriptors of the compounds were performed by DFT calculations. The energy gap (ΔE) = EHOMO – EHOMO for the studied compounds HYB, C3, C4, C1, and C2 were found to be 1.736, 1.243, 1.221 1.217, and 1.193 eV respectively. The chelated complexes exhibited higher DPPH radical scavenging power than the corresponding free HYB ligand. Amongst the complexes, C2 displayed the highest scavenging ability (IC50 = 2.59 ± 1.21 μM). Antimicrobial activities of the synthesized compounds were validated against bacterial strains: gram (+) E. faecalis and S. aureus; gram (−) P. aeruginosa and K. pneumoniae; and fungi: C. neoformans and C. albicans. C2 exhibited the most inhibition (MIC = 390.6 μg/mL) against P. aeruginosa and E. faecalis, while C1 acted as the most effective compound (MIC = 48.83 μg/mL) against the fungi strains. The docking study illustrated the highest binding affinity of −7.30 kcal/mol by C2 with P. aeruginosa (PDB: 8BN6), and C1 for the C. neoformans with −6.04 kcal/mol (PDB ID: 7T08) binding sites. Potential binding modes around the receptor\u27s active sites were predicted by the in silico molecular docking studies
Great Lakes Water Level Trends Using the Moving Statistics Method, with Implications for Climate Change and Cities
Get PDFIncreasing magnitudes of precipitation and evaporation are predicted for future climate change. Knowing whether these trends are occurring can help water managers plan with respect to future erosion, flooding, and design changes for shoreline infrastructure. Data from all the Laurentian Great Lakes (Erie, Michigan-Huron, Ontario, St. Clair, and Superior) were analyzed here to determine whether these trends are being realized. The MovingStatistics Method is used here using the moving average and moving standard deviation. It was found that Lakes Erie and St. Clair had the highest moving average trend of 0.5 mm/month, while Lake Ontario had the highest moving standard deviation trend (also 0.2 mm/month). Lake Superior had a decreasing moving average, while Lakes Erie, Michigan-Huron, and St. Clair had decreasing values of moving standard deviation. All lakes had moving average values greater than the measurement margin of error except Lake Superior. It is concluded that Great Lakes water levels have changed in the past and probably continue to change in the future. Property owners land managers can use these results to plan future budgets
Preparation and Microwave Deicing Properties of Ferric Oxide-Modified Emulsified Asphalt
No full textThis study addresses the challenge of icy asphalt pavements in cold climates by proposing an innovative and eco-friendly deicing material. Traditional approaches, such as salt spraying and mechanical deicing, often lead to environmental concerns and increased resource usage. In response, this paper introduces a novel ferric oxide-modified emulsified asphalt (FO-EA), formulated by integrating ferric oxide (FO) powder with emulsified asphalt (EA). Experimental results, including segregation tests and fluorescence microscopy, confirm that 20% by weight of FO is evenly dispersed in the EA. Remarkably, FO-EA-coated asphalt demonstrates a 50% reduction in microwave deicing time compared to conventional asphalt, with a significant increase in the heating rate of 0.12°C/s. In addition, FO-EA surpasses standard asphalt in skid resistance and water seepage tests, meeting all specification requirements. Furthermore, its deicing efficacy remains robust after 500 abrasion resistance test cycles. Overall, FO-EA emerges as an efficient and sustainable solution for road deicing
Improving rupture status prediction for intracranial aneurysms using wall shear stress informatics
Get PDFBACKGROUND: Wall shear stress (WSS) plays a crucial role in the natural history of intracranial aneurysms (IA). However, spatial variations among WSS have rarely been utilized to correlate with IAs\u27 natural history. This study aims to establish the feasibility of using spatial patterns of WSS data to predict IAs\u27 rupture status (i.e., ruptured versus unruptured). METHODS: Patient-specific computational fluid dynamics (CFD) simulations were performed for 112 IAs; each IA\u27s rupture status was known from medical records. Recall that CFD-simulated hemodynamics data (wall shear stress and its derivatives) are located on unstructured meshes. Hence, we mapped WSS data from an unstructured grid onto a unit disk (i.e., a uniformly sampled polar coordinate system); data in a uniformly sampled polar system is equivalent to image data. Mapped WSS data (onto the unit disk) were readily available for Radiomics analysis to extract spatial patterns of WSS data. We named this innovative technology WSS-informatics (i.e., using informatics techniques to analyze WSS data); the usefulness of WSS-informatics was demonstrated during the predictive modeling of IAs\u27 rupture status. RESULTS: None of the conventional WSS parameters correlated to IAs\u27 rupture status. However, WSS-informatics metrics were discriminative (p-value \u3c 0.05) to IAs\u27 rupture status. Furthermore, predictive models with WSS-informatics features could significantly improve the prediction performance (area under the receiver operating characteristic curve [AUROC]: 0.78 vs. 0.85; p-value \u3c 0.01). CONCLUSION: The proposed innovations enabled the first study to use spatial patterns of WSS data to improve the predictive modeling of IAs\u27 rupture status
Soil amendments alter tree growth and wood decay after forest thinning
Get PDFForest soil amendments are increasingly used in western US forests to dispose of unmerchantable woody residues, reduce wildfire risk, and improve soil properties. Our objective was to determine the effect of fertilizer and organic amendments on tree growth and organic matter decomposition after thinning. Treatments were a control, three single soil amendments (wood chips, fertilizer, and biochar), and one combined soil amendment (biochar + fertilizer), each applied after thinning a ponderosa pine (Pinus ponderosa Dougl. ex. Laws) stand. After 10 years, amendment treatments had no effect on tree diameter increment (p = 0.600), but the biochar + fertilizer and wood chip treatments significantly increased height growth (p = 0.006). To estimate belowground biological changes, we used wood stakes made from aspen (Populus tremuloides Michx.) and loblolly pine (Pinus taeda L.) as an index of microbial activity. Stakes were placed: (1) on top of the litter/amendments, (2) at the interface between the litter/amendments and mineral soil, and (3) vertically inserted into the mineral soil, and stake mass loss was measured over 5 years. Stake mass loss of each species was least on the soil surface and increased with increasing depth. Aspen stakes generally had greater mass loss at all three soil locations in the fertilizer and biochar treatments. In contrast, pine stake mass loss was lower than aspen and less affected by fertilizer. Using thinned tree biomass to create amendments can improve forest productivity by enhancing soil conditions and mitigating wildfire. However, the impact of amendments on tree growth may take decades to be detectable
Data Supporting Cloud Microphysical Response to Entrainment of Dry Air Containing Aerosols
No full textAerosol particles play a pivotal role in shaping clouds, precipitation, and climate. However, it still remains one of the significant uncertainties in climate change. While most aerosols are activated at the cloud base, the aerosol particles entrained from the cloud top or edges can also contribute to droplet formation above the base. This process might significantly impact cloud properties and lifetimes.
In this study, we investigate how entraining aerosol-laden air affects cloud microphysics by adding aerosol particles to the dry-air inflow in the Pi chamber experiments. The findings show that the cloud droplet number concentration and liquid water content increase substantially when the entrained air contains aerosol particles. Such an increase in L can be interpreted as a reduction in droplet sedimentation loss due to the presence of smaller droplets. The droplet size distribution (DSD) shifts toward smaller droplet sizes, and its width narrows more than the average droplet size, causing a decrease in relative dispersion (spectral narrowing). Moreover, the increased aerosol concentration in the entrained air diminishes the effective droplet radius, enhancing the cloud’s optical thickness and albedo—ultimately making the cloud appear brighter.
These results are particularly relevant to the entrainment interface at the top of stratocumulus clouds, where modeling studies suggest that sedimentation strongly influences L. Consequently, these results shed light on the implications of entraining aerosol-laden air for cloud formation, precipitation processes, and the broader climate system
Recycled filtered contaminants from liquid-fed pyrolysis as novel building composite material
No full textLiquid-fed pyrolysis allows the conversion of contaminated postconsumer plastic waste into valuable resources, removing contaminants through wax dissolution and filtration. One of the main challenges is currently represented by the management of its main byproduct, the contaminant-rich retentate from the filtration process. New circular economy strategies are needed to use this waste plastic-based composite as secondary raw materials. Despite the increasing trend in using plastic and plastic-waste composites for the building sector, there are currently limited applications of industrial recycling waste as engineering construction materials, e.g., from pyrolysis. This study evaluates the suitability of contaminant-rich retentate from liquid-fed pyrolysis of postconsumer multilayer packaging waste as novel composite materials for the building sector, taking advantage of its intrinsic composite nature. Thermogravimetric analysis was conducted to assess the composition of the retentate from filtration, a mixture of wax, polyethylene, polyethylene terephthalate, and aluminum. The compressive mechanical properties and densities were then evaluated on samples obtained through hot compression molding, using two batches to assess possible anisotropic behavior from the manufacturing process or the aluminum part orientation. The results indicate the suitability of the waste composite material for the building sector, reaching compression strengths (10–12 MPa) superior to construction bricks and brickworks (7 MPa), as well as 57 % lower density, 0.77 g/cm3. The ductile fracture behavior indicates its potential use for applications requiring failure prediction and safety constraints. This high strength-to-weight ratio composite represents a valuable alternative to virgin materials, showing potential for structural and aesthetic applications, including lightweight bricks, interior textured panels, decorative facades, and customized pavement tiles and slabs. Hot compression molding of pyrolysis waste composite paves the way for the real use of plastic-based composites from mixed and contaminated industrial waste in the building sector, contrasting resource depletion
Use of orthogonal treatment of acoustic attributes to study interaction effects in sound quality design
No full textTraditional methods of studying psychoacoustic attributes rely on subjective measurement of non-orthogonal sound samples. However, this approach has a narrow inference space due to the non-orthogonality of the acoustic attributes. This research aims to utilize an orthogonal treatment of acoustic attributes to study interaction effects in the sound quality of a fan-powered HVAC appliance by manipulating critical psychoacoustic attributes to create a broadened inference space. The results show that, in addition to the effects of loudness, sharpness, roughness, and prominence ratio, the roughness*prominence ratio, sharpness*prominence ratio, and the roughness*sharpness*prominence ratio interactions were statistically significant. Hence, this work demonstrates the importance of sound attribute interactions to consumers. Furthermore, comparing the empirical models without and with significant interactions demonstrated improvements in predicting the consumer response when including interaction effects. This work recommends considering psychoacoustic interactions, especially sharpness*roughness*prominence ratio, in designing products for improved consumer satisfaction