Search

Interface‐stabilizing polymers are frequently used in commercial applications to provide long‐lasting dispersions of colloids in liquid media. Dispersing high concentrations of pigments in aqueous solution can be particularly challenging. Here, we present a novel, fully hydrophilic dispersing agent system for carbon black (CB) pigments based on partially hydrolyzed poly(N‐vinylamides). These highly water‐soluble polymers adsorb onto CB through specific interactions between the polymer and surface‐bound moieties, rather than the hydrophobic effect. They participate in hydrogen bonding, ion–dipole interactions and can be partially positively charged to engage in ion pair formation, providing strong surface affinity. Dispersants are synthesized using free radical copolymerization of N‐vinylform‐ and ‐acetamide, acidic hydrolysis, and subsequent PEGylation. Molecular water solubility of the synthesized polymers is confirmed by using fluorescence spectroscopy. Highly concentrated CB dispersions are prepared in acidic, neutral, and basic media, which we identify to strongly affect the interactions between polymer and CB. The stability of CB dispersions is analyzed using ultracentrifugation and thermogravimetric analysis. The presented polymers are able to provide significantly more stable dispersions than a commercial reference product, showcasing the suitability of poly(N‐vinylamines) as potent CB dispersing agents. [ABSTRACT FROM AUTHOR]

Highlights Stemming from the cost‐effectiveness and broad applicability, many modification researches on Bisphenol A epoxy resin (DGEBA) and its carbon fiber composites have been done extensively. Here, following the concept of molecular composite, we prepared fully aminated p‐polyaramid with reactive amino side groups by polycondensation and reduction reaction, aiming to construct a molecular distribution of the reinforcement within the resin matrix and achieve a satisfactory enhancement effect. Among them, after adding 1 wt% fully aminated p‐polyaramid, Young's modulus and tensile toughness of the DGEBA epoxy resin (EP) increased significantly to 2.34 ± 0.03 GPa (+68.3%) and 4402 ± 213 kJ/m3 (+30.5%), the flexural modulus and toughness reached 4.14 ± 0.04 GPa (+42.8%) and 0.44 ± 0.01 J (+83.3%). Moreover, the Tg of EP was only decreased by 2.7°C. In addition, their warp‐knitted bidirectional carbon fiber composites also have enhancements in both flexural properties and interlaminar shear strength (all improved by more than 20%). What is noticeable is that the preparation and blending of fully aminated p‐polyaramid are simpler and more effective than most other micro‐ or nanofillers, and the dispersion is more uniform. Thus, it can act as a highly effective reinforcement and strengthen the properties of DGEBA and its carbon fiber composite materials significantly. Fully aminated p‐polyaramid is uniformly dispersed in EP by chemical bonds. DGEBA is strengthened and toughened without a significant decrease in Tg. The tensile and flexural modulus of EP is increased by 68.3% and 42.8%. Fully aminated p‐polyaramid can reinforce warp‐knitted carbon fiber composite. [ABSTRACT FROM AUTHOR]

This study successfully developed a bio-based, photocurable, anionic–nonionic dual-functional chain extender, and sulfonated cardanol-based polyethylene glycol (SCP), derived from renewable resources—cardanol and polyethylene glycol—for application in waterborne polyurethane dispersions (WPUDs). Utilizing SCP as a chain extender, WPUDs were prepared through a typical acetone process with poly(butylene adipate) (PBA), isophorone diisocyanate (IPDI), and ethylene diamine (EDA) at a constant NCO/OH ratio of 1:1. This research focused on the effects of polyethylene glycol molecular weight and SCP dosage on the particle size, stability, and film-forming properties of the WPUD. Optimal dispersion stability and film-forming performance were achieved with a polyethylene glycol molecular weight of 1500 and a PBA to SCP molar ratio of 4:1, yielding a particle size of 0.326 ± 0.010 μm and excellent storage stability over six months. The resulting WPU coatings exhibited a tensile strength of 11.4 MPa, which increased to 16.8 MPa after UV irradiation owing to the formation of a semi-interpenetrating network via the photopolymerization of cardanol's unsaturated side chains. UV cross-linking also enhanced water resistance, reducing the water absorption rate (WAR) from 18.68% to 4.21% and the water vapor transmission rate (WVTR) from 6.59 × 10−5 g·m⁻¹·Pa⁻¹·d⁻¹ to 2.26 × 10⁻⁵ g·m⁻¹·Pa⁻¹·d⁻¹, while also improving thermal stability. These findings demonstrate that SCP offers a sustainable and effective solution for developing high-performance WPU coatings. [ABSTRACT FROM AUTHOR]

This study focuses on formulating a low-surface-energy, water-resistant, and anti-condensation coating utilizing a fluorocarbon and acrylic resins composite (FAC), enhanced by six functional additives: antistatic agents, water-repellent agents, nanofillers, anti-mold and anti-algae agent, leveling agents, and wetting and dispersing agents. An orthogonal experimental design was implemented to systematically investigate the effects of varying concentrations of these additives on the surface tension of the coating. The results show that the optimized combination of fluorocarbon and acrylic resins composite (OFAC)with functional additives significantly reduces the surface tension, thereby improving both water resistance and anti-condensation properties. This research advances the development of more efficient surface treatment technologies, particularly for applications requiring enhanced water resistance and anti-condensation performance. [ABSTRACT FROM AUTHOR]

Direct ink writing (DIW) technology supersedes traditional mold‐based forming methods, significantly enhancing the fabrication of personalized and customized products with complex structures. This technology particularly excels in achieving precise control over the porosity of porous constructs. This study employs inorganic Al2O3 as raw material, sodium hexametaphosphate as dispersing agent, and inorganic SiO2 micropowder as binding medium to fabricate lattice porous structures. One challenge encountered is the viscoelastic behavior of the extruded filament. When spanning the unsupported segments of the lower layer, the upper extruded filaments are susceptible to deflection or collapse, adversely affecting the porosity and dimensional fidelity of the final specimens. Experimental results revealed that a larger span and smaller modulus will cause the extruded filament to be more prone to deformation at the midpoint. The introduction of 2 wt% polyethylene glycol as a plasticizer mitigates this issue, ensuring nondeflection of the extruded filaments at a span of 6 mm. The deflection model for the extruded filament about span and modulus identifies the minimum modulus necessary to prevent or minimize deflection under given spans, which closely approximates our experimental findings, offering a valuable framework for guiding the production of high‐precision, porosity‐controlled porous structures. [ABSTRACT FROM AUTHOR]

BACKGROUND: Surfactants, particularly non‐ionic ones, are widely used as adjuvants in pesticide formulations due to their ability to maintain pesticide effectiveness without changing solution properties, such as pH. While non‐ionic surfactants are generally low‐toxic, stable, and excellent dispersants with high solubilization capabilities, they may be less effective than cationic surfactants, which offer superior surface activity, transport properties, and antimicrobial action. This study investigates the efficacy of new piperidinium surfactants with carbamate fragments as adjuvants in insecticide formulations containing imidacloprid. The efficacy of these formulations is being assessed against greenhouse whitefly, a pest known to harm cultivated and ornamental flowering plants. RESULTS: The aggregation behavior of piperidinium surfactants containing carbamate fragments was investigated, and their wetting effect was evaluated. Synthesized surfactants have lower CMC values compared to their methylpiperidinium analogue. The effect of piperidinium surfactants on the insecticide concentration on the surface and inside tomato leaves was assessed using spectrophotometric methods. It was found that the introduction of piperidinium surfactants with carbamate fragment at a concentration of 0.1% wt. allows for decrease in lethal concentration of imidacloprid up to 10 times, thereby testifying the marked increase in the effectiveness of imidacloprid against the greenhouse whitefly insect pest (Trialeurodes vaporariorum). It was shown that the main factors responsible for the enhanced efficacy of the insecticide were the ability of the surfactant to increase the concentration of imidacloprid on the leaf surfaces and improve their penetration into the plant. CONCLUSION: The presented work employed a comprehensive approach, which significantly increases the generalizability of the results obtained and provides the ability to predict the effect and target selection of adjuvants. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The test samples are polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs), highly toxic and widely prevalent organic pollutants in natural waters. The feasibility of using dispersive liquid–liquid microextraction (DLLME) for extracting PCBs and PAHs, followed by their determination by GC–MS, was assessed in the presence of both contaminants. A DLLME method employing a binary dispersing agent was proposed, ensuring the simultaneous extraction of analytes with efficiency ranging from 80 to 97%. The proposed procedure enabled the GC–MS determination of 16 PAHs and 7 PCBs in natural waters in a wide concentration range of 2.0 × 10–5–0.04 µg/mL with an average error of 7–18% for PAHs and 11–18% for PCBs. The relative standard deviations for repeatability and reproducibility were found to be 3.1–6.5 and 4.3–7.7%, respectively, for PAHs, and 2.8–5.3 and 3.4–6.0%, respectively, for PCBs. [ABSTRACT FROM AUTHOR]

The coring data in high water‐cut oilfields indicates that the reservoir permeability will change continuously with water flooding, while the existing reservoir numerical simulation software cannot consider the time‐varying phenomenon of permeability. With the enhancement of reservoir heterogeneity, the near‐wellbore profile control fails to stabilize the oil production and control the water cut. The in‐depth profile control has been widely used in oilfields as a new technology, and the types of profile control agents are diverse, with a complex mechanism that cannot be effectively described by the existing conventional numerical simulation software. Considering these two phenomena comprehensively, a new three‐dimensional, three‐phase, six‐component mathematical model that can take into account the time‐varying phenomenon of reservoir permeability is proposed for a new kind of in‐depth profile control system, namely, the core–shell coagulation system, and an integrated numerical simulation software is developed. The mechanism of the in‐depth profile control system can be perfectly demonstrated in the simulator with time‐variation of permeability. The results of sensitivity analysis show that the effect is influenced by three factors: the mix slug injecting concentration, the coagulant aid slug volume, and the concentration of the suspension dispersing agent. [ABSTRACT FROM AUTHOR]

Simple Summary: Wild felids play a crucial role in maintaining the ecological balance within natural environments, which are increasingly affected by anthropogenic activities. Various viruses can infect these animals, and there are only two documented cases of Adenovirus occurrence in wild felids. This study aimed to detect Adenovirus DNA in fecal samples of wild felids from a remnant of the Atlantic Forest in southeastern Brazil. Adenovirus DNA presence was identified in four distinct fecal samples from jaguar (Panthera onca) and ocelot (Leopardus pardalis). This is the first report of this virus associated with Panthera onca. The viral DNA sequences were classified within the genus Mastadenovirus, specifically related to Mastadenovirus bosprimum and Mastadenovirus from the vampire bat Desmodus rotundus. We hypothesized that Adenoviruses were associated with the prey consumed, which may allow the felines to act as eventual viral dispersing agents, in addition to the risk of being infected. This study contributes to a better understanding of the occurrence and epidemiology of Adenoviruses in wild felids and their prey. A deeper understanding of these viruses within a One Health framework is crucial, given their relevance to animal health, human health, and environmental conservation. Wild felids are vital to maintaining the ecological balance in natural environments as they regulate prey populations at different levels of the food chain. Changes in the dynamics of predator populations can impact the entire biodiversity of an ecosystem. There are few reports of Adenovirus infections in these animals, and little is known about their epidemiology. Therefore, a deeper understanding of these viruses within a One Health framework is essential, given their importance to animal, human, and environmental health. This study aimed to detect Adenovirus DNA in fecal samples of wild felids from a remnant of the Atlantic Forest in southeastern Brazil, renowned for its high biodiversity. A total of 43 fecal samples, 11 from jaguar (Panthera onca) and 32 from ocelot (Leopardus pardalis), were collected. The samples were subjected to viral nucleic acid extraction and genetic material amplification through PCR, followed by nucleotide sequencing. All phylogenetic analyses were based on the amino acid sequences of the DNA polymerase and IV2a genes. Adenovirus DNA was detected in the feces of both species, with two samples of each feline testing positive. This study reports, for the first time, the occurrence of Adenovirus associated with feces of Panthera onca and Leopardus pardalis. All detected sequences were grouped within the Mastadenovirus genus. Based solely on phylogenetic distance criteria, the identified sequences could be classified as Mastadenovirus bosprimum and Mastadenovirus from the vampire bat Desmodus rotundus. We hypothesize that Adenoviruses were associated with the prey consumed, which may allow the felines to act as eventual viral dispersing agents in the environment, in addition to the risk of being infected. This study provides new information on the association of Adenoviruses with wild felids and their prey, and offers important insights into the ecological dynamics of these viruses in natural environments. It suggests that wild felines may play a crucial role in viral surveillance programs. [ABSTRACT FROM AUTHOR]

The distribution of lignin in forage was discussed in detail, the in vitro digestion of forage was analyzed, and the preparation methods of lignin was summarized. A new technical idea of enrichment of herbivorous animal excrement, purification of lignin and preparation of oxygen pressure leaching dispersant was put forward. By using herbivorous animals to digest, decompose and absorb nutrients such as protein, fat, starch and crude fiber in plants, lignin remains in the excrement and natural enrichment of lignin was realized. Lignosulfonate was prepared from herbivorous animal excrement, which increases the unit output of lignosulfonate and reduces the processing cost. This technology combines the characteristics of smelting enterprises and grassland ecology, makes full use of local grassland grass and herbivorous animal excrement to provide raw materials for preparing lignin for zinc oxygen pressure leaching, and forms a characteristic process combining plant-animal-zinc smelting in multiple fields [ABSTRACT FROM AUTHOR]

This investigation is inspired by multifunctional properties and biocompatibility of meglumine (ML) for new applications in colloidal processing of materials. The application of ML as both an alkalizer and capping agent enabled the fabrication of hydroxyapatite (HA) nanoparticles. The morphologies of HA nanoparticles prepared using ML alkalizer/capping agent or an inorganic alkali are compared. The use of ML allowed particle size reductions and offers multiple processing and environmental benefits. The feasibility of solubilization of alginic acid (ALH) biopolymer and glycyrrhetinic acid (GAH) drug in water using ML is demonstrated. For the first time, electrophoretic deposition (EPD) of ALH and GAH from their solutions is performed. The solubilization and EPD mechanisms are discussed, and the film deposition yield is analyzed. The use of ML as alkalizer, solubilizer, capping and dispersing agent facilitates the fabrication of ALH-GAH, ALH-HA, ALH-silica, and ALH-titania films by EPD. Changes in the EPD bath composition allows for the variation of the composition and microstructure of the films. The benefits of the suggested method for colloidal processing of composites are discussed. The use of ML opens an avenue for synthesis of other inorganic nanomaterials of controlled size, nanoparticle dispersion, solubilization, and EPD of other polymers, drugs, and composites. [ABSTRACT FROM AUTHOR]

Cutaneous metastatic melanoma (CMM) is the most aggressive form of skin cancer with a poor prognosis. Drug-induced secondary tumorigenesis and the emergency of drug resistance worsen an already worrying scenario, thus rendering urgent the development of new treatments not dealing with mutable cellular processes. Triphenyl phosphonium salts (TPPSs), in addiction to acting as cytoplasmic membrane disruptors, are reported to be mitochondria-targeting compounds, exerting anticancer effects mainly by damaging their membranes and causing depolarization, impairing mitochondria functions and their DNA, triggering oxidative stress (OS), and priming primarily apoptotic cell death. TPP-based bola amphiphiles are capable of self-forming nanoparticles (NPs) with enhanced biological properties, as commonly observed for nanomaterials. Already employed in several other biomedical applications, the per se selective potent antibacterial effects of a TPP bola amphiphile have only recently been demonstrated on 50 multidrug resistant (MDR) clinical superbugs, as well as its exceptional and selective anticancer properties on sensitive and MDR neuroblastoma cells. Here, aiming at finding new molecules possibly developable as new treatments for counteracting CMM, the effects of this TPP-based bola amphiphile (BPPB) have been investigated against two BRAF mutants CMM cell lines (MeOV and MeTRAV) with excellent results (even IC50 = 49 nM on MeOV after 72 h treatment). With these findings and considering the low cytotoxicity of BPPB against different mammalian non-tumoral cell lines and red blood cells (RBCs, selectivity indexes up to 299 on MeOV after 72 h treatment), the possible future development of BPPB as topical treatment for CMM lesions was presumed. With this aim, a biodegradable hyaluronic acid (HA)-based hydrogel formulation (HA-BPPB-HG) was prepared without using any potentially toxic crosslinking agents simply by dispersing suitable amounts of the two ingredients in water and sonicating under gentle heating. HA-BPPB-HA was completely characterized, with promising outcomes such as high swelling capability, high porosity, and viscous elastic rheological behavior. [ABSTRACT FROM AUTHOR]

Exploring high-efficiency catalyst toward hydrogen evolution reaction (HER) for sustainable hydrogen production is critical for building a forthcoming hydrogen economy. Atomically dispersed catalysts have shown great promises for catalyzing HER yet further fine-tuning the coordination chemical environment to boost the performance is still challenging. Herein, we report the synthesis and electrocatalytic HER application of Ru single atoms dispersed in P, N co-doped porous carbon (Ru SAs@PNC). Spherical aberration corrected scanning transmission electron microscope (AC-STEM) analysis revealed the formation of atomically dispersed Ru single atoms. The as-prepared Ru SAs@PNC catalyst showed excellent HER activity in 1 M KOH, evidenced by a small overpotential of 21 mV @ 10 mA cm−2 and a low Tafel slope of 31 mV dec−1, both of which are comparable to the Pt/C benchmark catalyst. It also exhibited great durability for long-time operation, as demonstrated by negligible overpotential increase in the 50 h E -t test, and outperformed stability in the accelerated durability test. Such excellent HER performance is mainly attributed to the N, P co-doped chemical coordination environment that differs from most widely reported solely nitrogen-coordinated Ru single atoms. [Display omitted] • A facile approach to prepare N, P codoped atomically dispersed Ru catalyst is reported. • The catalyst exhibits intriguing HER catalytic performance in alkaline solution. • DFT calculations revealed the reason of the HER enhancement upon P introduction. [ABSTRACT FROM AUTHOR]

AbstractIn this paper, the effect of carbon black (CB) on the mechanical and electromagnetic performance of cement-based materials was investigated using modified polyether for CB dispersion. Results show that, with suitable CB content and dispersant ratio, the average pore diameter and compressive strength will be decreased and improved with the adding of CB. Moreover, as CB content increases, the electrical conductivity of cement mortar decreases notably. Notably, at a 3% CB content, changes in the electromagnetic properties of cement mortar were observed. Below 3% CB content, dispersants reduce electromagnetic parameters and increase electrical conductivity. [ABSTRACT FROM AUTHOR]

In this study, high-performance zirconium carbide (ZrC) ceramics prepared by gel-casting method were reported for the first time. A water-based slurry with 40 vol% solids was prepared using TMAH and PVP as dispersants, and the resulting green body had a flexural strength of 21.11 ± 1.84 MPa after curing, which was sufficient for machining. Dense ZrC ceramics (relative density >97 %) were obtained by sintering at 2000 °C under atmospheric pressure, and a 387 ± 23.21 MPa flexural strength and 15.48 ± 0.28 GPa hardness were achieved. This study offers a new strategy for preparing ZrC ceramics with complex structures. [ABSTRACT FROM AUTHOR]

In this study, recycled carbon fibers (rCFs) recovered from waste carbon composites were used to manufacture wet-laid nonwoven fabrics. The aim was to improve dispersibility by investigating the changes in the dispersibility of carbon fibers (CFs) based on the content of the dispersant carboxymethyl cellulose (CMC) and the binder polyvinyl alcohol (PVA), and the length and basis weight of the CFs. In addition, the chemical property changes and oxygen functional group mechanisms based on the content of the CMC dispersant and PVA binder were investigated. The nonwoven fabrics made with desized CFs exhibited significantly improved dispersibility. For nonwoven fabrics produced with a fixed binder PVA content of 10%, optimal dispersibility was achieved at a dispersant CMC concentration of 0.4%. When the dispersant CMC concentration was fixed at 0.4% and the binder PVA content at 10%, the best dispersibility was observed at a CF length of 3 mm, while the maximum tensile strength was achieved at a fiber length of 6 mm. Dispersibility remained almost consistent across different basis weights. As the dispersant CMC concentration increased from 0.2% to 0.6%, the oxygen functional groups, such as carbonyl group (C=O), lactone group (O=C-O), and natrium hydroxide (NaOH), also increased. However, hydroxyl group (C-O) decreased. Moreover, the contact angle decreased, while the surface free energy increased. On the other hand, when the dispersant CMC concentration was fixed at 0.4%, the optimal binder PVA content was found to be 3%. As the binder PVA content increased from 0% to 10%, the formation of hydrogen bonds between the CMC dispersant and the PVA binder led to an increase in C=O and O=C-O bonds, while C-O and NaOH decreased. As the amount of oxygen increased, the contact angle decreased and the surface free energy increased. [ABSTRACT FROM AUTHOR]

Psychosocial research, which explores the unconscious and affective dynamics of organizational and social phenomena from critical perspectives, often adopts ethnographic methods. However, its locus, the unconscious, has an obscure, diffuse and dynamic nature that calls into question two central assumptions of conventional organizational ethnography: that an organization is a self-contained physical (research) site, and ethnographic research is best led by participant observation. The unconscious is produced by countless agents dispersed across time and space, making it impossible to readily identify a research site. Furthermore, psychosocial phenomena cannot be physically demarcated because a multitude of discourses, imagery, psyches, bodies, and objects are enmeshed in them. These raise contentious ontological, epistemological, and methodological questions for psychosocial researchers. In this article, we ruminate on "the field" in psychosocial organizational ethnography, seeking a robust epistemological and methodological approach to constructing and dwelling in an unconscious research site. Drawing on Lacanian psychoanalysis, we present a conceptual discussion of these issues and translate them into ethnographic methods illustrated by examples from the authors' research. By critically re-evaluating the question of "the field," we contribute to ethnographic studies of organizational phenomena with "fuzzy fields" without self-evident boundaries that draw on diverse onto-epistemologies. [ABSTRACT FROM AUTHOR]

The development of effective dispersants for nanoparticle suspensions is crucial for enhancing the performance and stability of various functional materials. In this study, we investigated a series of comb‐like block copolymers with well‐defined structures, including both categories of block copolymers and uniformly composed random copolymers, as dispersants for cerium oxide (CeO2) suspensions. Acrylic acid (AA) units were used for anchoring and electrostatic repulsion, while methoxy polyethylene glycol acrylate (MPEGA) units provided additional steric hindrance and solubility. We explored stabilization mechanisms involving polymer topologies, chain lengths, compositions, and molecular interactions from kinetic and thermodynamic perspectives. The results demonstrate significant improvements in dispersion stability with both categories of well‐controlled copolymers, especially with uniformly composed random copolymers due to their uniformly distributed multi‐point anchoring and balanced electrostatic and steric stabilization. This research not only enhances the fundamental understanding of polymer‐nanoparticle interactions and polymer dispersants, but also provides valuable guidance for the tailored design of dispersants for specific industrial and scientific needs. [ABSTRACT FROM AUTHOR]

Graphene oxide and polyaniline have some unique properties and are considered as new generation materials for various applications. One major application of these materials is the adsorption of pollutants. In this study, Graphene oxide was synthesized with different levels of oxidation by using the modified Hummers method. Polyaniline/graphene oxide composite was synthesized by in situ polymerization with GO loading at 10% and 50% and further the composite is casted inside a disposable syringe by using N-methyl-2-pyrrolidone (NMP) as a dispersing agent. An adsorption experiment was carried out for water containing pesticide chlorpyrifos. The produced materials were characterized by FTIR spectroscopy & and XRD. Morphology was studied by SEM images. The FTIR spectra shows the formation of functional groups like -OH, -COOH on graphene, which may increase the hydrophilicity and adsorption properties. FTIR spectra of the composite portrayed the formation of bonds between polyaniline and graphene oxide. XRD peaks were obtained corresponding to crystals of polyaniline and graphite sheets. The adsorption efficiency was determined by analysis of water samples before and after filtration by using GC-MS. The composite produced with 50% amount of GO showed optimum results for the removal of chlorpyrifos. However, the composite with 10% GO loading is showing very low efficiency for the removal of chlorpyrifos. The PANI/GO composite is a possible candidate for the treatment of river water polluted by agricultural pollutants. [ABSTRACT FROM AUTHOR]

Introduction: Chitosan membranes with glycerol can function as an effective dispersing agent for different antibiotics or active ingredients that can be used in the treatment of diseases present in the oral cavity. Methods: The effects of the addition of glycerol on the mechanical, water absorption, swelling, pH, thickness, disintegration, rugosity, and antibacterial properties of chitosan-chlorhexidine-glycerol membranes were investigated in this study. Results and discussion: Mechanical results indicated that chitosan membranes' rugosity, strength, flexion, and thickness differed at loading 1, 3, 5, 10, 15, and 20% of glycerol (p < 0.05). The chitosan membranes' rugosity, dissolution, strength, and pH results were significantly enhanced by the presence of glycerol at 3, 5, and 10% concentrations. In this investigation, the antimicrobial activity model used was the inhibition of Streptococcus mutans CDBB-B-1455 by chitosan-chlorhexidinemembranes. It was observed that there was no change in inhibition with different concentrations of glycerol. The results suggest that chitosan-glycerol-chlorhexidine membranes may be a potential candidate for topical antiseptic application in buccal-dental disorders caused by S. mutans, such as caries, periodontal diseases, and oral squamous cell carcinoma, helping to prevent the development of serious conditions that can compromise human health. [ABSTRACT FROM AUTHOR]

The goal of this work was to develop acrylonitrile–butadiene (NBR) elastomer composites filled with hydroxyapatite (HAP) characterized by improved cure characteristics and resistance to burning. Silane, i.e., (3-aminopropyl)-triethoxysilane, ionic liquid, i.e., 1-decyl-3-methylimidazolium bromide and surfactant, i.e., cetyltrimethylammonium bromide, were used to improve the filler's dispersibility in the elastomer matrix and to reduce the time and temperature of vulcanization. The effects of HAP and dispersants on the cure characteristics, crosslink density and physico–chemical properties of NBR composites were explored. The additives used, especially the ionic liquid and surfactant, effectively improved the dispersion of HAP in the NBR matrix. The amount of HAP and the dispersant used strongly affected the cure characteristics and crosslink density of NBR. The optimal vulcanization time significantly increased with HAP content and was pronouncedly reduced when ionic liquid and surfactant were applied. In addition, ionic liquid and surfactant significantly lowered the onset vulcanization temperature and improved the crosslink density and hardness of the vulcanizates while impairing their elasticity. HAP and dispersants did not significantly affect the damping properties or chemical resistance of NBR vulcanizates. Above all, application of HAP considerably enhanced the resistance of vulcanizates to thermo-oxidative aging and reduced their flammability compared with the unfilled NBR. [ABSTRACT FROM AUTHOR]

Over the last few years, graphene oxide (GO) has stood out as an ideal carbon‐filler to dope polymer matrix, specifically conductive polymers. This paper investigates the possibility of producing ternary nanocomposites based on a conductive polymer poly(3,4 ethylene dioxythiophene) polystyrene sulfonate (PEDOT:PSS), doped with graphene oxide (GO) and is additivated with a green dispersing and reducing agent (ascorbic acid). Three‐component inks have been developed and their rheological and surface tension properties are studied to evaluate their filmability. Subsequently, through the drop‐casting technique, thin films of the inks are produced, and their electrochemical behavior is deeply analyzed via cyclic voltammetry tests (CV). Particularly, PEDOT:PSS/GO/AA ink shows a higher specific capacitance (Csp) up to 29.84 mF cm−2 than pristine PEDOT:PSS, suggesting that this ink can be used as an electrode material for supercapacitor devices. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the effect of carbon nanotubes on the electromagnetic shielding and electrical conductivity of polyetheretherketone(PEEK). The modified multi-walled carbon nanotubes (mMWCNT) was prepared using cetyltrimethylammonium bromide (CTAB) as a dispersing agent. The PEEK/mMWCNT composits were prepared by the processing technology of wet mixing and extrusion blending. The results showed that the mMWCNT were well-dispersed in PEEK matrix, which provided strong support for improving the mechanical and electrical properties of the composites. When the mMWCNT mass fraction was lower than 2.0%, the mechanical properties of PEEK/mMWCNT composites were significantly improved. The mMWCNT formed a 3D network with good conductivity in PEEK. In terms of electromagnetic shielding performance, the total electromagnetic shielding efficiency of PEEK/mMWCNT composites ranged from 3.35 dB to 24.47 dB, which indicated a good absorption of X-band electromagnetic waves. This study confirmed that PEEK/mMWCNT composites have superior electrical conductivity and electromagnetic shielding properties. Hence, the composites have a wide application potential in electronic equipment, communication technology and military protection. [ABSTRACT FROM AUTHOR]

Significant research has been conducted to minimise environmental impacts and promote the sustainable use of resources and raw materials. Microbial surfactants are an example of advanced materials obtained from sustainable production processes. In the present study, a biosurfactant was produced by the yeast Starmerella bombicola ATCC 22214 grown in a previously selected low-cost mineral medium containing 10% sucrose, 1.2% canola oil, and 0.5% corn steep liquor. The biosurfactant reduced surface tension from 72 ± 0.1 to 32.76 ± 0.3 mN/m. The yield was 23 g/L, and the critical micelle concentration was 0.6 g/L. The biosurfactant emulsified 96.25 ± 0.08% of used motor oil, was characterised as a sophorolipid, and exhibited stability under extreme conditions with no significant loss of its properties. Toxicity was assessed by exposing the microcrustacean Artemia salina and the zebrafish (Danio rerio) to the biosurfactant. The biosurfactant proved efficient for use in remediation processes, removing 97.8% and 69.2% of the petroleum derivative from sand in kinetic and static tests, respectively, and removed 91.5% of the contaminant from seawater. The results indicate the potential of this new biosurfactant for the mobilisation and solubilisation of hydrocarbons in the marine environment. This green biomolecule is a promising technology for the replacement of chemical dispersants in the remediation of aquatic and soil systems. [ABSTRACT FROM AUTHOR]

An interpolation method, which estimates unknown values with constrained information, is based on mathematical calculations. In this study, we addressed interpolation from an image-based perspective and expanded the use of image inpainting to estimate values at unknown points. When chemical gas is dispersed through a chemical attack or terrorism, it is possible to determine the concentration of the gas at each location by utilizing the deployed sensors. By interpolating the concentrations, we can obtain the contours of gas concentration. Accurately distinguishing the contours of a contaminated region from a map enables the optimal response to minimize damage. However, areas with an insufficient number of sensors have less accurate contours than other areas. In order to achieve more accurate contour data, an image inpainting-based method is proposed to enhance reliability by erasing and reconstructing low-accuracy areas in the contour. Partial convolution is used as the machine learning approach for image-inpainting, with the modified loss function for optimization. In order to train the model, we developed a gas diffusion simulation model and generated a gas concentration contour dataset comprising 100,000 contour images. The results of the model were compared to those of Kriging interpolation, one of the conventional spatial interpolation methods, finally demonstrating 13.21% higher accuracy. This suggests that interpolation from an image-based perspective can achieve higher accuracy than numerical interpolation on well-trained data. The proposed method was validated using gas concentration contour data from the verified gas dispersion modeling software Nuclear Biological Chemical Reporting And Modeling System (NBC_RAMS), which was developed by the Agency for Defense Development, South Korea. [ABSTRACT FROM AUTHOR]

In recent decades, wood drying has emerged as an important method to ensure wood quality and improve wood utilization. However, the addition of modifiers to wood can hinder the transfer of moisture, making the drying process difficult. Therefore, the drying of modified wood is challenging. This study focuses on poplar wood and reports the preparation of modified wood capable of releasing health-beneficial negative oxygen ions. In particular, this study examined the effect of hexacyclite on the transfer of internal moisture and heat in wood. Hexacyclite was dispersed using sodium hexametaphosphate as a dispersing agent, and the modified poplar wood was prepared via vacuum pressure impregnation. The process involved six cycles of the following treatments: a vacuum treatment (−0.08 MPa, 20 min), followed by a pressure treatment (1 MPa, 120 min), and a final atmospheric treatment (5 min). The modified wood was dried via kiln drying, during which the overall wood temperature rapidly increased, with the total drying rate also increasing by 1.05%/h. The introduction of hexacyclite potentially altered the way modified wood bound with moisture, leading to permanent changes in the porosity of cell walls and the structure of polymers and thus altering the movement of water molecules. The modified wood continuously emitted far-infrared rays with a wavelength of 8–15 μm. In some large water clusters, after the far-infrared energy was absorbed, the movement of water molecules accelerated, thereby increasing the drying rate in the wood below the fiber saturation point. Ultimately, this resulted in the modified wood drying faster and thus exhibiting a better quality. [ABSTRACT FROM AUTHOR]

The present study examines the impacts of saponin, extracted from the fruits of Acacia Concinna, in its effectiveness as a dispersant and stabilizer during the pipeline conveyance of iron ore particles. The basic fundamental characteristics of iron ore, which comprises a majority of hematite and has a size of (≤75 µm), have been examined and characterized. Iron ore water slurry (IWS) rheological behavior has been investigated as a function of saponin doses, pH, particle concentration, and the shear rate-shear stress correlation. The change in zeta potential with pH is used to compute the isoelectric point of IWS. An appropriate mechanism has been presented to explicate the interaction between saponin and particles of Iron ore. The surface-modified particles exhibit improved dispersion characteristics in the aqueous solution due to the modification of electrostatic force that the surface charge on each particle causes. Investigation indicates that the optimal proportion of saponin had a significant favorable effect on the fluidity and stability of the suspension. The analysis of the economic impact of the dispersant has been conducted through the evaluation of slurry head loss and specific energy consumption (SEC) pertaining to the implementation of the IWS pipeline in its intended commercial application. [ABSTRACT FROM AUTHOR]

The adhesion of clay to the cutterhead and cutters presents a significant challenge during earth pressure balance (EPB) shield excavation in clay strata. Dispersants are widely used to remove clay that adheres to metal surfaces, but their conditioning characteristics and working mechanisms have not yet been thoroughly investigated. This study investigated the effects of organic and inorganic dispersants on clay plasticity and slaking characteristics through Atterberg limit and slaking tests, complemented by Zeta potential and swelling tests to explore the underlying mechanisms. The results demonstrate that increasing the content of inorganic and organic dispersants reduces soil plasticity and enhances the slaking rate during the rapid development period in pure water. Dispersion slaking occurs in pure water for soil blocks treated with inorganic dispersant, while soil blocks treated with organic dispersant undergo primarily surface slaking. A higher organic dispersant concentration significantly intensified the slaking rate. In contrast, inorganic dispersant solutions inhibit soil slaking. Inorganic dispersant solutions impede soil expansion and slaking due to reduced electrostatic repulsion and increasing difficulty in water infiltration. Conversely, organic dispersant solutions accelerate soil slaking by promoting soil expansion and solution infiltration, reducing surface tension, and increasing pore air pressure. [ABSTRACT FROM AUTHOR]

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bacterial biofilms commonly cause chronic and persistent infections in humans. Bacterial biofilms consist of an inner layer of bacteria and an autocrine extracellular polymeric substance (EPS). Biofilm dispersants (abbreviated as dispersants) have proven effective in removing the bacterial physical protection barrier EPS. Dispersants are generally weak or have no bactericidal effect. Bacteria dispersed from within biofilms (abbreviated as dispersed bacteria) may be more invasive, adhesive, and motile than planktonic bacteria, characteristics that increase the probability that dispersed bacteria will recolonize and cause reinfection. The dispersants should be combined with antimicrobials to avoid the risk of severe reinfection. Dispersant-based nanoparticles have the advantage of specific release and intense penetration, providing the prerequisite for further antibacterial agent efficacy and achieving the eradication of biofilms. Dispersant-based nanoparticles delivered antimicrobial agents for the treatment of diseases associated with bacterial biofilm infections are expected to be an effective measure to prevent reinfection caused by dispersed bacteria. Key points: • Dispersed bacteria harm and the dispersant's dispersion mechanisms are discussed. • The advantages of dispersant-based nanoparticles in bacteria biofilms are discussed. • Dispersant-based nanoparticles for cutting off reinfection in vivo are highlighted. [ABSTRACT FROM AUTHOR]

Nanocellulose, a nanoscale derivative from renewable biomass sources, possesses remarkable colloidal properties in water, mechanical strength, and biocompatibility. It emerges as a promising bio-based dispersing agent for various nanomaterials in water. This mini-review explores the interaction between cellulose nanomaterials (nanocrystals or nanofibers) and water, elucidating how this may enable their potential as an eco-friendly dispersing agent. We explore the potential of nanocellulose derived from top-down processes, nanocrystals, and nanofibers for dispersing carbon nanomaterials, semiconducting oxide nanoparticles, and other nanomaterials in water. We also highlight its advantages over traditional methods by not only effectively dispersing those nanomaterials but also potentially eliminating the need for further chemical treatments or supporting stabilizers. This not only preserves the exceptional properties of nanomaterials in aqueous dispersion, but may even lead to the emergence of novel hybrid functionalities. Overall, this mini-review underscores the remarkable versatility of nanocellulose as a green dispersing agent for a variety of nanomaterials, inspiring further research to expand its potential to other nanomaterials and applications. [ABSTRACT FROM AUTHOR]

In this paper, the dispersion of Carbon nanomaterials (CNMs) in an electrolytic solution containing cations such as Ca2+, Al3+, Na+, and Mg2+ with different types of superplasticizers (Sika, Master Ease 3502, Prime DC, and Prime Flow) have been investigated. Further, the stabilized CNMs along with different superplasticizers (Sps) incorporated into the cementitious mortar and studied their mechanical strength. The influence of Sps on the stability of CNMs in an aqueous medium has been monitored by UV-Visible spectroscopy. The study concludes that Sika Sp was the best dispersant for the CNMs dispersion in an aqueous medium. The de-stability of the CNMs has followed this trend of the agglomerations in the electrolytic solution as Al3+>Ca2+>Mg2+>Na+. The Sika Sp has great dispersant properties as well as provides a homogeneous distribution of CNMs in a cementitious matrix which was supported by FE-SEM analysis. The addition of SIKA@PPC-GO (GO about 0.0015% by weight of cement) and SIKA@PPC-FCNTs (FCNTs about 0.0015% by weight of cement) results in enhancement of cement 11.67%, 8.73% for compressive and 26.35, 20.61% for tensile strength respectively, at the curing ages of 90 days. This investigation may provide advanced knowledge to predict the stability of CNMs in superplasticizer-based solutions. [ABSTRACT FROM AUTHOR]

The use of natural additives in pipeline transportation has gained significant attention in recent years due to their potential to enhance the stability and rheology of the suspension. In this study, the dispersing and stabilizing properties of the saponin extracted from the fruits of Sapindus laurifolia are examined in the pipeline transportation of limestone. The physicochemical, morphological, and flow characteristics of limestone samples less than 75 μm are determined. The rheological behaviors of the suspension have been examined by varying the shear rate, solid, and dispersion concentrations. The critical micelle concentration of the dispersant was determined to be 1.8 wt%. In the tested concentration ranges of 40–70%, the Hershel–Bulkley model best matched the data. When the surfactant was added to the suspension, the water's surface tension was lowered, increasing the wettability of the limestone particles and decreasing particle-particle contact. Increases in zeta potential measurements confirmed that the steric component primarily stabilizes limestone water suspension. Finally, the dispersant's economic impact was studied depending on slurry head loss and specific energy consumption. [ABSTRACT FROM AUTHOR]

This research mainly investigated the flotation kinetics of molybdenite in seawater based on four flotation models. Molybdenite flotation presented an excellent agreement with the first-order model with rectangular distribution. The ultimate cumulative recovery (R∞) and flotation rate constant (k) of molybdenite decreased in seawater, mainly due to the divalent cations, with the impact of Mg2+ being significantly greater than that of Ca2+. The addition of sodium silicate (SS) and sodium hexametaphosphate (SH) increased the flotation recovery and rate, probably due to the positive role of dispersants on preventing the attachment of seawater precipitates onto molybdenite surface. In addition, three different stages of flotation kinetics were proposed to reveal the molybdenite flotation for the first time, with the highest flotation recovery and rate being found at Stage I. However, seawater showed a negative role on Stage I, i.e. resulting in a longer duration and lower recovery, as compared to that in pure water. The addition of both SS and SH improved the flotation kinetics at Stage I, with SH being more significant. Therefore, it is more feasible to eliminate the negative effects of seawater on molybdenite flotation at the initial stage (Stage I). [ABSTRACT FROM AUTHOR]

This research focuses on the application of nanocellulose-stabilized silver nanoparticles (AgNPs) as a colorimetric sensing probe for mercury (II) detection. For this purpose, cellulose nanocrystals (CNCs) and cellulose nanofibers (CNFs) were employed with dual functions: a stabilizing agent and a dispersing matrix. The chemical and structural properties of the samples were analysed by various techniques such as XRD, FTIR, TEM and UV–Vis Spectroscopy. Due to different morphologies and surface functional groups in each type of nanocellulose, their effects on the AgNP formation as well as their response against mercury (II) ions were studied. It was discovered that the AgNPs stabilized by both types of nanocellulose can provide high sensitivity and selectivity towards mercury (II) ions. However, some interference caused by iron (III) ions was observed. This interference could be significantly reduced if the CNFs were employed during the AgNP preparation. Therefore, the advantage of using the CNFs as a stabilizing agent as well as a dispersing matrix will be discussed in detail. Furthermore, the possibility of fabrication into solid-state platforms (nanopapers) and response to mercury (II) ions will be demonstrated. [ABSTRACT FROM AUTHOR]

A detailed understanding of the interactions between wax and asphaltenes with other components of crude oils and the effect of treatments with paraffin inhibitors (PIs) and asphaltene dispersants (ADs), with a focus on identifying specific structure-activity relationships, is necessary to develop effective flow assurance strategies. The morphological and rheological consequences of treating wax and asphaltenes in oils of differing composition with a series of ADs having structural features in common with an alpha olefin-maleic anhydride (AO-MA) comb-like copolymer PI were assessed alone and in combination with said PI. Of the four ADs studied, two were identified as being effective dispersants of asphaltenes in heptane-induced instability tests and in a West Texas (WT) crude. The degree to which a low concentration of asphaltenes stabilizes wax in the absence of treatment additives is lessened in oils having greater aromatic fractions. This is because these stabilizing interactions are replaced by more energetically favorable aromatic–asphaltene interactions, increasing oil viscosity. Treatment with AD alone also reduces the extent of wax–asphaltene interactions, increasing oil viscosity. In concert with the PI, treatment with the AD having greater structural similarity with the PI appears to improve wax solubility in both the presence and absence of asphaltenes. However, the viscosity of the treated oils is greater than that of the oil treated with PI alone, while treatment with AD having lesser structural similarity with the PI does not adversely affect oil viscosity. These data suggest that rather than treating both wax and asphaltenes, AD may poison the function of the PI. These data illuminate the pitfalls of designing flow assurance additives to interact with both wax and asphaltenes and developing treatment plans. [ABSTRACT FROM AUTHOR]

The intensity of light scattered by liquids has been studied for over a century since the valuable microscopic information about the molecules can be obtained, such as the anisotropy of the molecular polarizability tensor or preferred orientations of neighboring molecules. However, in modern dynamic light scattering experiments, the scattering intensity is usually disregarded, unlike in dielectric spectroscopy, which can be considered as a complementary experimental method, where the dielectric strength is routinely evaluated. The reason lies partly on the fact that the exact form of the equations relating the macroscopically measured light scattering intensity to the microscopic properties of the molecules is debated in the literature. Therefore, as a first step, we compare anisotropy parameters from the literature, calculated from light scattering intensities using different equations, with quantum chemical calculations for over 150 medium-sized molecules. This allows us to identify a consistent form of equations. In a second part, we turn to the depolarized light scattering spectra of 13 van der Waals liquids and some mixtures thereof, recorded with a combination of Tandem–Fabry–Perót and Raman spectroscopies, giving direct access to the reorientational dynamics of the molecules. We discuss how the strength of the structural α-relaxation is connected to the anisotropy parameter, what implication this has for the shape of the α-relaxation, how the components of a mixture—also for the case of ionic liquids—can be identified in this way, and how orientational correlation parameters can be extracted. Additionally, we point out for the example of n-alkanes that for highly flexible molecules, the reorientational motion might not be the decisive source of the depolarized scattered light. We also show that light scattering might serve as a sensitive tool to check the accuracy of a conformer ensemble obtained by quantum chemical calculations. [ABSTRACT FROM AUTHOR]

The aim of this work was application of the hydroxyapatite (HAP) in various amounts by weight as a filler of natural rubber (NR) biocomposites. Innovatively, silanes, that is, (3‐aminopropyl)‐triethoxysilane (APTES) and bis[3‐(triethoxysilyl)propyl] tetrasulfide (TESPTS), surfactant, that is, cetyltrimethylammonium bromide (CTAB), and alkylimidazolium ionic liquids (ILs) with halide anions, that is, 1‐butyl‐3‐methylimidazolium chloride (BmiCl) and 1‐decyl‐3‐methylimidazolium bromide (DmiBr), were used to improve the dispersion of the HAP and curatives particles in the rubber matrix, and consequently the curing characteristics and properties of NR biocomposites. The influence of HAP and dispersants on the crosslink density, tensile properties, thermal stability, resistance to thermo‐oxidative aging, and ability to damp vibration of vulcanizates were investigated. It has been proven, that HAP can be efficiently used as a filler of NR biocomposites alternatively to commercial inactive or active fillers, for example, chalk, talc, or silica. The optimal HAP content is 30 phr. HAP did not detrimentally affect the curing characteristics of NR composites, crosslink density, and damping properties of the vulcanizates, while significantly raised their tensile strength, thermal stability, and resistance to thermo‐oxidative aging. Most importantly, CTAB and ILs considerably improved the dispersion of HAP and curatives particles in the NR matrix and consequently lowered the vulcanization temperature by approximately 25°C and enhanced by approximately 50% the crosslink density and tensile strength of the NR biocomposites. [ABSTRACT FROM AUTHOR]

The precipitation and deposition of asphaltenes are significant challenges in the petroleum industry resulting in substantial costs. A practical approach to addressing this issue is to use chemicals as inhabiting and dispersing agents. Zwitterionic surfactants are interesting materials in this field. In this study, three zwitterionic compounds including 2-(1-methyl-1H-imidazol-3-ium-3-yl)butane-1-sulfonate (MIBS), 4-(pyridin-1-ium-1-yl) butane-1-sulfonate (PBS), and 4-(tributylammonio)butane-1-sulfonate (TBBS) were synthesized and characterized by FT-IR, NMR spectroscopy, thermogravimetric, and differential thermal analysis. The ability of these zwitterions to prevent asphaltenes precipitation was investigated using interfacial measurements, ultraviolet spectroscopy, quartz microbalance analysis, particle size analysis, and optical microscopy. The results showed that the MIBS zwitterion, which contains an imidazole cation, was the most effective in dispersing asphaltene aggregates compared to the other two zwitterions. For instance, the UV spectroscopy results showed that the dispersion indexes for MIBS, PBS, and TBBS were 52.8%, 29.9%, and 16.3%, respectively. In addition, the size of asphaltene particles reached from 2179 nm to 622, 1489, and 2038 nm for MIBS, PBS, and TBBS, respectively. Finally, a comparison between the performance of these zwitterions with sodium dodecyl sulfonate (SDS) and tetrabutylammonium hydrogen sulfate (TBAHS) showed the following trend: MIBS (90.5%)> PBS (79.4%) > TBAHS (75%)> SDS (73.9%) >TBBS (46%). [ABSTRACT FROM AUTHOR]

This study examined the effects of starting material dispersion on the formation of AlN powder synthesized by carbothermal reduction-nitridation (CRN) route. After preparing aqueous and non-aqueous slurries containing 6.5 vol % of Al 2 O 3 and carbon black powder with/without a dispersant, the particle dispersion was evaluated by sedimentation and viscosity measurements. The zeta potential was also measured to determine the optimal dispersion conditions for electrostatic repulsion because carbon black is challenging to disperse in water, owing to its low surface charge and poor wettability. The aqueous slurry prepared with 5 wt % Gen0451 dispersant at pH = 10 showed the highest degree of dispersion. Complete AlN conversion was achieved by nitridation at 1600 °C for 6 h under 10 L/min N 2 flow. This result clearly showed the importance of starting material dispersion on the synthesis of AlN by CRN, demonstrating the feasibility of aqueous processing instead of conventional solvent-based processing. [ABSTRACT FROM AUTHOR]

Sorting single‐walled carbon nanotubes (SWNTs) that are heterogeneous into homogeneous groups based on their electronic type, chirality, and handedness is crucial for optoelectronic and biological applications. To achieve this, researchers have utilized dispersants with different binding affinities to sort SWNTs according to their chiralities. This review article provides an overview of the methods developed for sorting SWNTs using dispersants, with a particular focus on the role played by dispersant binding affinities. The article is organized into six sections, including an introduction, a background on SWNTs and dispersant‐based individualization of SWNTs, information on dispersants and their binding affinities, separation methods for SWNTs based on controlling the dispersant binding affinity, parameters used to control dispersant binding affinity, and a conclusion. It is hoped that this review will enhance understanding of the intricate interactions between dispersants and SWNTs, leading to the development of new SWNT sorting methods for future applications. [ABSTRACT FROM AUTHOR]

Polycarboxylate (PCE) superplasticizers are the most important additive in concrete, which can effectively improve the workability of cement slurry. Different from the traditional regarding of PCEs as dispersants, here, we understand the PCEs as nano‐lubricants. By employing the molecular dynamics simulation, a sophisticated model was used to evaluate the interfacial friction between the C–S–H particles. The results reveal that the PCEs can reduce the interfacial friction between the C–S–H particles, and thus increase the fluidity of cement slurry. Further analyses infer the role of PCE segments in lubrication. The carboxylates on PCEs ensure the anchoring and hinder the separation of Ca ions. The side chains are used to lubricate the C–S–H surface, due to the weak adsorption between the side chains and the C–S–H surface. Predictably, this study not only provides a method to directly evaluate the performance of PCEs but also suggests new insights into the colloid dispersion of the low‐water content system. [ABSTRACT FROM AUTHOR]

A series of comb polymers poly(2-(dimethylamino)ethyl methacrylate (DMAEMA)-co-methacrylic acid (MAA)-co-methoxy polyethylene glycol methacrylate (MPEGMA)) (poly(DMAEMA-MAA-MPEGMA, DMM) were synthesized and used as N-methyl-2-pyrolidinone (NMP)-based lithium iron phosphate (LFP) suspension dispersants. The effects of the grafting density of the carboxyl group as the anchoring group and the chain length of the side chain of PEG, which plays the role of spatial site resistance, on the rheological properties and suspension stability of the slurry were systematically investigated. By investigating the adsorption amount and thickness of DMM on the LFP surface, combined with calculations based on the scalar law and Flory theory, the molecular structure of the comb polymer dispersant was revealed to influence the adsorption and dispersion performance. The dispersion of LiFePO4 was due to the synergistic effects of adsorption and steric hindrance effect, which resulted that dispersants with medium carboxyl density and PEG side chain length can improve the dispersion performance and stability. [ABSTRACT FROM AUTHOR]

Natural pigment violacein exhibits many pharmaceutical properties which include antimicrobial, anticancer and antioxidant activities. However, limited solubility of violacein in water has restricted its application. Hence, in this study, the violacein nanoparticles were synthesised via sonication technique with the aid of surfactants as dispersing and stabilising agent. Experimentally, the effect of surfactant and violacein concentrations on the production, size and stability of violacein nanoparticles was studied. The location of the violacein in the surfactant micelle was studied using computational study. Violacein nanoparticles were successfully produced at optimized parameters, surfactant concentration of 1 mM, concentration of violacein of 50 µg/mL and sonication time of 10 min. The smallest violacein nanoparticles were 131.5 ± 2.001 nm, with PDI of 0.180 ± 0.018, which indicated a monodispersed violacein nanoparticle distribution. The violacein nanoparticles were stable upon dispersion in water, with a zeta potential of − 49.8 ± 3.49 mV. Violacein was located in the hydrophobic tail region of SDS surfactant micelle after 92 ns. The violet colour of the nanoparticles was maintained at pH from 3 to 11, temperature up to 60 °C and under dark condition, despite its nanoscale size. Higher degradation rate was observed at high temperature and upon light illumination, with k = 6.51 × 10−3 h−1, t1/2 = 106 h and k = 6.75 × 10−4 h−1, t1/2 = 1027 h, respectively, following the first-order kinetics. As conclusion, the violacein nanoparticles were able to be produced using water as a medium for green approach, and the nanoparticle colour remained stable at various conditions. This study provides an insight into the molecular mechanism of violacein-surfactant interaction for its solubility and stability in water. [ABSTRACT FROM AUTHOR]

Solid oxide fuel cells (SOFCs) are a green energy technology that offers a cleaner and more efficient alternative to fossil fuels. The efficiency and utility of SOFCs can be enhanced by fabricating miniaturized component structures within the fuel cell footprint. In this research work, the parallel-connected inter-digitized design of micro-single-chamber SOFCs (µ-SC-SOFCs) was fabricated by a direct-write microfabrication technique. To understand and optimize the direct-write process, the cathode electrode slurry was investigated. Initially, the effects of dispersant Triton X-100 on LSCF (La0.6Sr0.2Fe0.8Co0.2O3-δ) slurry rheology was investigated. The effect of binder decomposition on the cathode electrode lines was evaluated, and further, the optimum sintering profile was determined. Results illustrate that the optimum concentration of Triton X-100 for different slurries was around 0.2–0.4% of the LSCF solid loading. A total of 60% of solid loading slurries had high viscosities and attained stability after 300 s. In addition, 40–50% solid loading slurries had relatively lower viscosity and attainted stability after 200 s. Solid loading and binder affected not only the slurry's viscosity but also its rheology behavior. Based on the findings of this research, a slurry with 50% solid loading, 12% binder, and 0.2% dispersant was determined to be the optimal value for the fabricating of SOFCs using the direct-write method. This research work establishes guidelines for fabricating the micro-single-chamber solid oxide fuel cells by optimizing the direct-write slurry deposition process with high accuracy. [ABSTRACT FROM AUTHOR]

Unusual events trigger persistent spikes in uncertainty. Standard models cannot match these dynamic patterns. This paper presents a unified framework, motivated by the literature on inattention. Agents choose whether and how to prepare for different possible states of the world by collecting information. Agents optimally ignore sufficiently unlikely events, so the occurrence of such events does not resolve, but rather increases, uncertainty. Uncertain agents have dispersed beliefs, making it harder to focus future preparation. Thus, uncertainty begets uncertainty for an inattentive agent, endogenously persisting. In a financial application, this framework matches patterns in volatility, volume of trade, belief dispersion, and spreads. This paper was accepted by Victoria Ivashina, finance. Supplemental Material: The data file is available at https://doi.org/10.1287/mnsc.2023.4836. [ABSTRACT FROM AUTHOR]

In this paper, EFKA FA 4663 (EFKA) dispersant was used for the first time in the alumina slurries tert-butyl alcohol-based freeze-casting and compared to the commonly used anionic dispersant citric acid (CA). The comparison of both dispersants was analyzed at the beginning of the process at different ultra-low freezing temperatures (− 170 to − 130 °C). The monoliths obtained with EFKA presented promising properties due to its stabilization of alumina particles by both electrostatic interactions and steric impediment, a considerable improvement when compared to the CA that promotes the stabilization of alumina particles only by electrostatic interaction. The use of different dispersants, as well as the control of freezing temperature, significantly influenced the microstructural properties of the monoliths. The monoliths exhibited prismatic pore geometry with high connectivity, forming a complex pore channel with total porosity up to 64.7%, and open porosity up to 48.5%. Results confirmed that the modification of the type of dispersant led to a difference in the grain size (up to 23.1%) and pore size (up to 30.5%) obtained in the materials. The monoliths produced with EFKA dispersant presented a considerable compressive strength resistance up to 11.7 MPa due to its dispersion mechanism that provided the thickening of the walls, confirming that the type of dispersion has a strong influence on the final properties of the materials. Therefore, the type of dispersant proved to be another parameter that allows the refinement of alumina monoliths properties, highlighting the use of EFKA as a promising alternative in the system studied. [ABSTRACT FROM AUTHOR]

The research on the application of nanofluids in the thermal management of electric components is gaining widespread attention. In this context, and as past studies on nanofluids mainly focus on thermal properties, the investigation of the electrical properties of nanofluids has become important. The role of dispersants on the electrical conductivity of nanofluids stabilized using two biopolymer dispersants, chitosan, and gum arabica (GA), and a synthetic dispersant Sodium Dodecyl Benzoic Sulfate (SDBS) is investigated in this work. The nanofluids are prepared with water, nanoparticles (0.1 wt%), and dispersants (0.05 and 0.5 wt%), and the electrical conductivity is measured to examine the role of nanoparticle materials (CuO, Fe3O4, and CuO + Fe3O4), dispersants, and temperatures (25–40 °C). According to observations, the dispersants significantly affect the electrical conductivity, while nanoparticle material has a minimal impact. At 0.5 wt% concentration, SDBS stabilized nanofluids have electrical conductivity 708.7 times higher than water, whereas, with chitosan and GA, it is 144.2 and 12.8 times higher than water, respectively. CuO-water nanofluids show relatively higher electrical conductivity than Fe3O4 and hybrid CuO + Fe3O4 water nanofluids. Measured electrical conductivity is used for regression analysis using response surface methodology (RSM). Three quadratic nonlinear polynomial equations are developed to predict the electrical conductivity based on the input parameters (dispersant concentration and temperature). The predicted and measured values were in excellent agreement with each other. The current study offers a novel perspective on the electrical behavior of nanofluids with biopolymer dispersants and provides a prediction model for nanofluid electrical conductivity. [ABSTRACT FROM AUTHOR]

Catastrophic oil spill is one of the major issues to the environment. Various methods have been used to treat oil spillage including in situ burning, the use of skimmers, dispersants, bioremediation, dispersing agents, oil sorbents, and biological agents. Application of oil sorbent is one of the effective solutions in oil spill clean-up. Polymers are sustainable extraordinary materials for the treatment of oil spillage due to their special physicochemical characteristics such as high porosity, good hydrophobicity, and reusability. Polymers are modified using suitable chemical reagents and their hydrophobicity is enhanced, making them suitable for oil spill clean-up. The present manuscript is an attempt to summarize the study of chemical modifications done on a polymer polyurethane (PU) for achieving the desirable properties, for efficient oil spill clean-up. A patent analysis has been carried out for the leading countries, top inventors, leading assignees, trends of patent publications, citation analysis, and summary of granted patents in the area of the use of a polymer Polyurethane (PU) for oil spill clean-up. [ABSTRACT FROM AUTHOR]