Three functional relationships differentiate radial surface roughness between clutch killer and normal use samples based on the influence of friction radius and pv.
To valorize residual lignins generated in biorefineries and pulp and paper mills, the creation of lignin-based admixtures (LBAs) for cement-based composites provides a novel solution. Consequently, LBAs have taken on growing importance as a domain of research during the past decade. This study examined the bibliographic data related to LBAs, using a scientometric analysis method and a comprehensive qualitative discussion process. Employing a scientometric approach, 161 articles were selected for this investigation. Upon scrutinizing the abstracts of the articles, a selection of 37 papers dedicated to the creation of novel LBAs underwent a meticulous and critical evaluation. LBAs research's key characteristics, including prominent publications, recurring themes, prominent researchers, and participating countries, were highlighted by the science mapping. In terms of classification, LBAs developed so far include plasticizers, superplasticizers, set retarders, grinding aids, and air-entraining admixtures. Qualitative review indicated that the majority of research projects had a core focus on constructing LBAs using Kraft lignins from the pulp and paper industry. read more Ultimately, the residual lignins generated by biorefineries require enhanced attention, since their profitable application serves as a pertinent strategy for nations possessing large biomass reserves. Studies regarding LBA-reinforced cement-based composites primarily focused on production procedures, chemical analysis, and primary fresh-state evaluation. Further studies are imperative to better evaluate the practicality of different LBAs, and to incorporate the multidisciplinary character of this subject, therefore necessitating an evaluation of hardened-state properties. This holistic analysis of research progress in LBAs is designed to benefit early-stage researchers, industry experts, and grant awarding bodies. This research also helps us grasp lignin's influence on sustainable construction strategies.
Promising as a renewable and sustainable lignocellulosic material, sugarcane bagasse (SCB) is the principle residue of the sugarcane industry. Value-added products can be produced from the cellulose, which is found in SCB at a proportion of 40-50%, for deployment in diverse applications. A comparative investigation into green and conventional approaches for cellulose extraction from the SCB by-product is undertaken. This work juxtaposes green extraction methods (deep eutectic solvents, organosolv, hydrothermal processing) with traditional methods (acid and alkaline hydrolysis). The treatments' efficacy was evaluated based on the extract yield, the chemical constituents, and the physical structure. A review of the sustainable nature of the most promising cellulose extraction methodologies was also completed. Autohydrolysis, in comparison to the other proposed cellulose extraction methods, showed the greatest promise, yielding a solid fraction with a value around 635%. A substantial 70% portion of the material is cellulose. The solid fraction exhibited a 604% crystallinity index and the usual cellulose functional groups. An E(nvironmental)-factor of 0.30 and a Process Mass Intensity (PMI) of 205 confirmed that this approach was environmentally sound, according to the evaluated green metrics. For economically and environmentally sound extraction of a cellulose-rich extract from sugarcane bagasse (SCB), autohydrolysis proved to be the superior approach, directly contributing to the valorization of this abundant byproduct.
In the last decade, researchers have meticulously investigated the ability of nano- and microfiber scaffolds to promote wound healing, the regrowth of tissues, and the safeguarding of the skin. The straightforward mechanism of the centrifugal spinning technique, enabling the production of copious fiber, makes it the preferred method over alternative techniques. In the quest for optimal polymeric materials for tissue applications, further exploration of those with multifunctional characteristics is essential. This study's literature review examines the core process of fiber generation, exploring the effects of manufacturing parameters (machine and solution) on resulting morphologies such as fiber diameter, distribution, alignment, porosity, and the resultant mechanical properties. Furthermore, the underlying physics behind the form of beads and the formation of uninterrupted fibers are briefly examined. This study accordingly summarizes the recent developments in centrifugally spun polymer fiber technology, emphasizing its structural properties, performance characteristics, and role in tissue engineering applications.
Composite material additive manufacturing is advancing through advancements in 3D printing; by merging the physical and mechanical properties of multiple components, a novel material suitable for numerous applications is produced. This research assessed the consequence of incorporating Kevlar reinforcement rings on the tensile and flexural characteristics of Onyx (nylon-carbon fiber) composite. The mechanical response of additively manufactured composites under tensile and flexural testing was investigated by regulating variables such as infill type, infill density, and fiber volume percentage. Evaluation of the tested composites demonstrated a four-fold improvement in tensile modulus and a fourteen-fold improvement in flexural modulus over the Onyx-Kevlar composite, exceeding the pure Onyx matrix's properties. Experimental data demonstrated an uptick in the tensile and flexural modulus of Onyx-Kevlar composites, facilitated by Kevlar reinforcement rings, leveraging low fiber volume percentages (under 19% in both samples) and 50% rectangular infill density. Although delamination and other imperfections were identified, a more thorough examination is crucial to yield products that are free from errors and that are reliable in real-world environments, such as those encountered in the automotive or aeronautical industries.
For controlled fluid flow during Elium acrylic resin welding, the resin's melt strength is paramount. read more This investigation examines the effects of butanediol-di-methacrylate (BDDMA) and tricyclo-decane-dimethanol-di-methacrylate (TCDDMDA) on the weldability of acrylic-based glass fiber composites, with the goal of achieving a suitable melt strength for Elium through a subtly implemented crosslinking method. Elium acrylic resin, an initiator, and multifunctional methacrylate monomers, in a range of 0 to 2 parts per hundred resin (phr), comprise the resin system that permeates the five-layer woven glass preform. Vacuum infusion (VI) fabrication of composite plates occurs at ambient temperatures, followed by infrared (IR) welding. Composite materials containing multifunctional methacrylate monomers at concentrations exceeding 0.25 parts per hundred resin (phr) display a significantly low strain level under thermal conditions ranging from 50°C to 220°C.
Parylene C, possessing attributes like biocompatibility and its consistent conformal covering, finds significant use in the domains of microelectromechanical systems (MEMS) and electronic device encapsulation. However, the material's inferior adhesion and low thermal stability restrict its widespread application. A novel approach, involving the copolymerization of Parylene C and Parylene F, is presented in this study to enhance both the thermal stability and adhesion of Parylene on silicon. The proposed method yielded a copolymer film with an adhesion strength 104 times higher compared to the Parylene C homopolymer film. Moreover, the Parylene copolymer films' friction coefficients and cell culture properties were investigated. The Parylene C homopolymer film exhibited no degradation, as indicated by the results. This copolymerization methodology substantially increases the range of applications for Parylene materials.
To diminish the environmental effects of the construction sector, it is essential to lessen greenhouse gas emissions and repurpose industrial byproducts. Ground granulated blast furnace slag (GBS) and fly ash, industrial byproducts with sufficient cementitious and pozzolanic properties, offer a concrete binder alternative to ordinary Portland cement (OPC). read more This critical analysis examines the influence of several key parameters on the compressive strength of concrete or mortar, composed of alkali-activated GBS and fly ash binders. Strength development is analyzed in the review, taking into account the curing environment, the mix of ground granulated blast-furnace slag and fly ash in the binding material, and the concentration of the alkaline activator. The article additionally explores the correlation between exposure to acidic media and the age of specimens at the time of exposure, in relation to the development of concrete's strength. Acidic environments' impact on mechanical characteristics was determined to be contingent upon the specific acid employed, in addition to the alkaline activator's composition, the proportions of ground granulated blast-furnace slag (GBS) and fly ash in the binder, and the sample's age at exposure, among various other variables. Through a focused review of the literature, the article identifies critical observations about the changing compressive strength of mortar/concrete when cured under moisture-loss conditions versus curing in environments that retain the alkaline solution and reactants for hydration and the formation of geopolymer products. Slag and fly ash concentrations in blended activators directly affect the magnitude and speed of strength development. A critical review of the existing literature, along with a comparative study of the research findings, and an identification of the reasons for agreement or disagreement in the conclusions, constituted the research methodologies employed.
A growing concern in agriculture involves water scarcity and the loss of fertilizer from agricultural lands through runoff, thus polluting other areas.