ABSTRACT
The use of municipal solid waste incineration fly ash, commonly referred to as "fly ash", as a supplementary cementitious material (SCM), has been explored to mitigate the CO2 emissions resulting from cement production. Nevertheless, the incorporation of fly ash as an SCM in mortar has been shown to weaken its compressive strength and increase the risk of heavy metal leaching. In light of these challenges, this study aims to comprehensively evaluate the influence of CO2 pressure, temperature, and residual water/binder ratio on the CO2 uptake and compressive strength of mortar when combined with fly ash. Additionally, this study systematically examines the feasibility of mechanochemical pretreatment, which enhances the homogenization of fly ash and augments the density of the mortar's microstructure. The results indicate that the use of mechanochemical pretreatment leads to a notable 43.6% increase in 28-day compressive strength and diminishes the leaching of As, Ba, Ni, Pb, Se, and Zn by 17.9-77.8%. Finally, a reaction kinetics model is proposed to elucidate the CO2 sequestration process under varying conditions. These findings offer valuable guidance for incorporating fly ash as an SCM and CO2 sequestrator in mortar.
Subject(s)
Metals, Heavy , Refuse Disposal , Solid Waste/analysis , Coal Ash , Carbon Dioxide , Incineration , Metals, Heavy/analysis , Carbon , Refuse Disposal/methods , Particulate MatterABSTRACT
The cellular uptake and simulated intestinal wall transportation of resveratrol-loaded zein/pectin nanoparticles were assessed using Caco-2 cells and monolayers, respectively. The oral bioavailabilities of encapsulated (En-RES) and free (RES) resveratrol were evaluated by monitoring the resveratrol concentration in rat plasma after oral administration. The impact of encapsulation on the anti-inflammatory activity of the resveratrol was determined using lipopolysaccharide (LPS)-treated RAW 264.7 macrophages. The cellular uptake of encapsulated resveratrol increased appreciably with observation time (1-4 h), reaching a maximum value (≈1.06 µg mL-1) after 2 h, whereas that of free resveratrol (in DMSO) only increased slightly, reaching 0.62 µg mL-1 after 4 h. The transmembrane transport of En-RES was significantly higher than that of RES (p < 0.05): the resveratrol concentration in the receiving compartment of Costar trans-wells was 4.7-fold higher for the encapsulated resveratrol. The resveratrol concentration in the plasma of rats was measured after they were fed formulations containing a resveratrol equivalent of 20 mg per kg bodyweight. The plasma level reached a maximum value of 1.35 ± 0.26 µg mL-1 at 4 h after feeding the En-RES formulation, and then decreased to 0.19 ± 0.04 µg mL-1 after 48 h. Conversely, the plasma level only reached a maximum value of 0.31 ± 0.05 µg mL-1 at 0.5 h after feeding the free resveratrol formulation (an aqueous PEG 400 solution), and was totally cleared after 8 h. Cell culture studies suggested that En-RES exhibited a strong anti-inflammatory activity by inhibiting the production of NO, PGE2, IL-1ß, IL-6, TNF-α, promoting IL-10 release, inhibiting expression of TLR4, and inhibiting phosphorylation of JNK, ERK1/2, p38 and MAPK. Overall, this research suggests that zein-pectin core/shell nanoparticles are a highly effective delivery system for resveratrol, significantly increasing its bioavailability and anti-inflammation activity. These oral delivery systems may be particularly suitable for applications in functional foods or pharmaceuticals.
Subject(s)
Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/pharmacokinetics , Resveratrol/pharmacology , Resveratrol/pharmacokinetics , Animals , Area Under Curve , Biological Availability , Caco-2 Cells , Cell Survival/drug effects , Cytokines/genetics , Cytokines/metabolism , Dietary Supplements , Enzyme-Linked Immunosorbent Assay , Gene Expression Regulation/drug effects , Half-Life , Humans , Inflammation/drug therapy , Inflammation/metabolism , Lipopolysaccharides/toxicity , Mice , Nitric Oxide , RAW 264.7 Cells , Rats , Rats, Sprague-Dawley , Toll-Like Receptor 4/genetics , Toll-Like Receptor 4/metabolismABSTRACT
A series of V2O5/TiO2-carbon nanotube (CNT) catalysts were prepared and tested to decompose gaseous 1,2-dichlorobenzene (1,2-DCBz). Several physicochemical methods, including nitrogen adsorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and H2 temperature-programmed reduction (TPR) were employed to characterise their physicochemical properties. To better understand the effect of CNT properties on the reactivity of V2O5/TiO2-CNT catalysts, the 1,2-DCBz residue remaining in the off-gas and on the catalyst surface were both collected and analysed. The results indicate that the outer diameter and the surface functional groups (hydroxide radical and carboxyl) of CNTs significantly influence upon the catalytic activity of CNT-containing V2O5/TiO2 catalysts: the CNT outer diameter mainly affects the aggregation of CNTs and the π-π interaction between the benzene ring and CNTs, while the introduction of -OH and -COOH groups by acid treatment can further enlarge specific surface area (SSA) and contribute to a higher average oxidation state of vanadium (V aos) and supplemental surface chemisorbed oxygen (Oads). In addition, the enhanced mobility of lattice oxygen (Olatt) also improves the oxidation ability of the catalysts.