Pulp and paper wastewater sludges are waste streams produced in major quantities across the world. The recycling of these organic sludges, for example to soil amendments, is desired in the circular economy but carries the risk of potential pollutants to be also introduced into the environment. Pulp and paper wastewater sludges have been scarcely studied matrices in the microplastic research due to their complex composition.
View Article and Find Full Text PDFBacterial nanocellulose (BC) has attracted significant attention across a wide array of applications due to its distinctive characteristics. Recently, there has been increasing interest in leveraging waste biomass to improve sustainability in BC biogenesis processes. This study focuses on optimizing the citrus pulp waste (CPW) medium to enhance BC production using .
View Article and Find Full Text PDFEpoxidized natural rubber (ENR) offers a unique combination of strength, sustainability, and versatile structure, making it a good candidate for creating sacrificial and reformable bonds via secondary curatives. These curatives should be simple and compatible with other rubber ingredients and industrial mixing processes. Although many alternative curatives, including zinc chloride, zinc dimethacrylate (ZDMA), and sebacic acid (SA), have been proven to be successful, they have never been compared in the same compound.
View Article and Find Full Text PDFSewage sludge is produced during municipal wastewater treatment and can be further treated to be used for soil applications due to its high nutrient and carbon content. Anaerobic digestion is often used to manage sewage sludge. However, sewage sludge has a high load of microplastics that can be transferred to the soil, causing a burden to the environment.
View Article and Find Full Text PDFBacterial nanocellulose (BC) is a highly versatile biopolymer currently pursued as a material of choice in varied themes of biomedical and material science research fields. With the aim to extend the biotechnological applications, the genetic tractability of the BC producers within the Komagataeibacter genus and its potential as an alternative host chassis in synthetic biology have been extensively studied. However, such studies have been largely focused on the model Komagataeibacter spp.
View Article and Find Full Text PDFThe analysis of microplastics in complex environmental samples requires the use of chemicals to reduce the organic matrix. This procedure should be evaluated in terms of the preservation of the microplastic's integrity, typically done with pristine reference microplastics. However, real microplastics are most likely degraded due to weathering, so pristine reference microplastics might not depict the appropriateness of the process.
View Article and Find Full Text PDFThe extraction of microplastics from complex environmental matrices, such as sewage sludge, has proven challenging because of their high organic content. A common procedure for the extraction of microplastics from sludge involves conducting a chemical digestion to reduce the amount of organic matter in the sample, followed by a density separation of microplastics. In order to increase the reliability of the density-based separation, an optimisation of the chemical digestion is needed.
View Article and Find Full Text PDFCurrently, the vast majority of composite waste is either landfilled or incinerated, causing a massive burden on the environment and resulting in the loss of potentially valuable raw material. Here, conventional pyrolysis and reactive pyrolysis were used to reclaim carbon fibers from aeronautical scrap material, and to evaluate the feasibility of using reclaimed carbon fibers in structural components for the automotive sector. The need for fiber sizing was investigated as well as the behavior of the fiber material in macroscopic impact testing.
View Article and Find Full Text PDFIcephobic coatings interest various industries facing icing problems. However, their durability represents a current limitation in real applications. Therefore, understanding the degradation of coatings under various environmental stresses is necessary for further coating development.
View Article and Find Full Text PDFspp. has been used for the bioconversion of industrial wastes and lignocellulosic hydrolysates to bacterial cellulose (BC). Recently, studies have demonstrated the capacity of spp.
View Article and Find Full Text PDFMost of the properties of epoxy resins are tied to their degree of cross-linking, making understanding the reactivity of different epoxy systems a crucial aspect of their utilization. Here, epoxy-amine reactivity is studied with density functional theory (DFT) at various cut-off levels to explore the suitability of the method for estimating the reactivity of specific epoxy systems. Although it is common to use minimal structures in DFT to reduce computational cost, the results of this study highlight the important role of hydrogen bonding and other noncovalent interactions in the reactivity.
View Article and Find Full Text PDFAramid fibers are high-strength and high-modulus technical fibers used in protective clothing, such as bulletproof vests and helmets, as well as in industrial applications, such as tires and brake pads. However, their full potential is not currently utilized due to adhesion problems to matrix materials. In this paper, we study how the introduction of mechanical adhesion between aramid fibers and matrix material the affects adhesion properties of the fiber in both thermoplastic and thermoset matrix.
View Article and Find Full Text PDFThe doping of halide perovskite nanocrystals (NCs) with manganese cations (Mn ) has recently enabled enhanced stability, novel optical properties, and modulated charge carrier dynamics of the NCs host. However, the influence of Mn doping on the synthetic routes and the band structures of the host has not yet been elucidated. Herein, it is demonstrated that Mn doping promotes a facile, safe, and low-hazard path toward the synthesis of ternary Cs Bi I NCs by effectively inhibiting the impurity phase (i.
View Article and Find Full Text PDFMost recycling methods remove the essential sizing from reinforcing fibres, and many studies indicate the importance of applying sizing on recycled fibres, a process we will denote here as resizing. Recycled fibres are not continuous, which dissociates their sizing and composite lay-up processes from virgin fibres. In this study, commercial polypropylene and polyurethane-based sizing formulations with an aminosilane coupling agent were used to resize recycled glass and carbon fibres.
View Article and Find Full Text PDFTo enable and/or facilitate analysis of microplastics from environmental samples, a purification process is required to reduce the organic matter content. The development of such process has as one main concern, besides achieving efficient organic matter reduction, the preservation of the microplastics. In this study, a three-step method for sewage sludge purification was proposed employing sodium dodecyl sulfate and hydrogen peroxide.
View Article and Find Full Text PDFThe focus of this paper is the realization and verification of a modified fiber bundle pull-out test setup to estimate the adhesion properties between threads and elastic matrix materials with a more realistic failure mode than single fiber debond techniques. This testing device including a modified specimen holder provides the basis for an adequate estimation of the interlaminar adhesion of fiber bundles including the opportunity of a faster, easier, and more economic handling compared to single fiber tests. The verification was done with the single-fiber and microbond test.
View Article and Find Full Text PDFExposure to metal oxide nanomaterials potentially occurs at the workplace. We investigated the toxicity of two Fe-oxides: FeO nanoparticles and nanorods; and three MFeO spinels: NiZnFeO, ZnFeO, and NiFeO nanoparticles. Mice were dosed 14, 43 or 128 μg by intratracheal instillation.
View Article and Find Full Text PDFDetonation nanodiamonds, also known as ultradispersed diamonds, possess versatile chemically active surfaces, which can be adjusted to improve their interaction with elastomers. Such improvements can result in decreased dielectric and viscous losses of the composites without compromising other in-rubber properties, thus making the composites suitable for new demanding applications, such as energy harvesting. However, in most cases, surface modification of nanodiamonds requires the use of strong chemicals and high temperatures.
View Article and Find Full Text PDFNanocellulose and chitosan have recently started to get attention as environmentally friendly piezoelectric materials for sensor and energy harvesting applications. Conversely, current commercially available flexible piezoelectric films made of for example polyvinylidene difluoride (PVDF) are relatively expensive and made from non-renewable materials. We measured the piezoelectric responses (2-8 pC/N) for solvent casted films based on nanocellulose, microcrystalline chitosan and their blends.
View Article and Find Full Text PDFAmorphous titanium dioxide (a-TiO) combined with an electrocatalyst has shown to be a promising coating for stabilizing traditional semiconductor materials used in artificial photosynthesis for efficient photoelectrochemical solar-to-fuel energy conversion. In this study we report a detailed analysis of two methods of modifying an undoped thin film of atomic layer deposited (ALD) a-TiO without an electrocatalyst to affect its performance in water splitting reaction as a protective photoelectrode coating. The methods are high-temperature annealing in ultrahigh vacuum and atomic hydrogen exposure.
View Article and Find Full Text PDFIn this paper, we propose and verify a theoretical model of the development of dispersion quality of aqueous carbon nanotube (CNT) colloid as a function of sonochemical yield of the sonication process. Four different surfactants; Triton X-100, Pluronic F-127, CTAB and SDS were studied. From these four SDS had the lowest dispersion performance which was surprising.
View Article and Find Full Text PDFIn this work, we report about the mechanical relaxation characteristics of an intrinsically self-healable imidazole modified commercial rubber. This kind of self-healing rubber was prepared by melt mixing of 1-butyl imidazole with bromo-butyl rubber (bromine modified isoprene-isobutylene copolymer, BIIR). By this melt mixing process, the reactive allylic bromine of bromo-butyl rubber was converted into imidazole bromide salt.
View Article and Find Full Text PDFACS Appl Mater Interfaces
June 2017
Some bacterial strains such as Komagataeibacter xylinus are able to produce cellulose as an extracellular matrix. In comparison to wood-based cellulose, bacterial cellulose (BC) holds interesting properties such as biodegradability, high purity, water-holding capacity, and superior mechanical and structural properties. Aiming toward improvement in BC production titer and tailored alterations to the BC film, we engineered K.
View Article and Find Full Text PDFThe preparation of weblike titanium dioxide thin films by atomic layer deposition on cellulose biotemplates is reported. The method produces a TiO web, which is flexible and transferable from the deposition substrate to that of the end application. Removal of the cellulose template by calcination converts the amorphous titania to crystalline anatase and gives the structure a hollow morphology.
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