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In this paper, a novel rubber nanocomposite containing phenyl-vinyl-methyl-polysiloxane (PVMQ) and ethylene propylene diene monomer (EPDM) was produced during a two-roll mill procedure for mechanical applications. For this purpose, ethylene propylene diene monomer-grafted-maleic anhydride compatibilizer (EPDM-g-MAC) and graphene oxide (GO) was used as a compatibilizer and reinforcements to make a uniform composite. To study mechanical and physical characterizations, dynamic mechanical thermal analysis (DMTA), rheology, morphology, and curing characterizations of nanocomposites were investigated, which showed that compatibilizer makes GO dispersion uniformly. An electrical resistivity test was performed to study the electrical conductivity of the nanocomposites. The results indicate that the samples with higher GO content had a response to the electrical current. The curing study indicates that, by increasing the GO nanoparticles in the presence of EPDM-g-MAC, the curing properties are enhanced as well as mechanical properties by improving the bonding among GO, compatibilizer, and matrix [tensile strength (54%), modulus (68%), elongation-at-break (67%), hardness (81%), and fatigue (51%)]. FE-SEM and TEM images demonstrated that, by increasing GO nanoparticles in the presence of compatibilizer, the mean diameter of EPDM decreased in the substrate, which consequently increased the mechanical properties. The changes in surface temperature were investigated with constant voltage (75 V), which indicates that by increasing GO nanoparticles and electrical conductivity, the surface temperature increased significantly. The results of practical experiments showed good agreement with the theoretical results. [ABSTRACT FROM AUTHOR]

Hyperglycemia, a distinguishing feature of diabetes mellitus that might cause a diabetic foot ulcer (DFU), is an endocrine disorder that affects an extremely high percentage of people. Having a comprehensive understanding of the molecular mechanisms underlying the pathophysiology of diabetic wound healing can help researchers and developers design effective therapeutic strategies to treat the wound healing process in diabetes patients. Using nanoscaffolds and nanotherapeutics with dimensions ranging from 1 to 100 nm represents a state‐of‐the‐art and viable therapeutic strategy for accelerating the wound healing process in diabetic patients, particularly those with DFU. Nanoparticles can interact with biological constituents and infiltrate wound sites owing to their reduced diameter and enhanced surface area. Furthermore, it is noteworthy that they promote the processes of vascularization, cellular proliferation, cell signaling, cell‐to‐cell interactions, and the formation of biomolecules that are essential for effective wound healing. Nanomaterials possess the ability to effectively transport and deliver various pharmacological agents, such as nucleic acids, growth factors, antioxidants, and antibiotics, to specific tissues, where they can be continuously released and affect the wound healing process in DFU. The present article elucidates the ongoing endeavors in the field of nanoparticle‐mediated therapies for the management of DFU. Significance statement: To sum up, this study emphasizes that it may be feasible to develop better treatments for improperly healed diabetic wounds by studying the molecular mechanics of diabetic wound healing. As new products, nanomaterials can transfer nucleic acids, growth factors, antioxidants, and antibiotics to specified tissues for continuous release. Moreover, nanomaterials are more likely to interact with biological systems and infiltrate wound sites due to their smaller diameter and larger surface area. Hence, nano‐scaffolds and nano‐therapeutics can accelerate diabetic wound healing. [ABSTRACT FROM AUTHOR]

Summary: This paper investigates design of an adaptive fixed‐time fault‐tolerant decentralized controller for a class of uncertain multi‐input multi‐output (MIMO) switched large‐scale non‐strict interconnected systems under arbitrary switching subject to unknown control directions, quantized nonlinear inputs, actuator failures unknown external disturbances, and unmodeled dynamics. In addition to interconnected terms, time‐varying delayed interconnected terms have been considered in the system model which makes it more general than previous works in the literature. The proposed controller can handle switched systems with unknown switching signal and different types of input nonlinearities including, saturation, backlash, and dead‐zone. The singularity problem in designing the fixed time controller has been solved. The quantizer and actuators fault parameters are assumed to be unknown. The Razumikhin lemma has been used to deal with the delayed interconnected terms. To cope with the system unknown dynamics, neural networks (NNs) have been applied and by updating the maximum norms of the networks weight vectors the computational load has been reduced. The explosion of complexity occurring in the traditional back‐stepping technique has been avoided by applying dynamic surface control (DSC). Finally, by defining an appropriate common Lyapunov function (CLF), fixed‐time convergence of system outputs and the closed‐loop system stability have been established. The effectiveness of the proposed controller has been shown via simulation study. [ABSTRACT FROM AUTHOR]

In this work, simultaneous inferential control of particle size distribution (PSD) and molecular weight distribution (MWD) in a semi-batch emulsion polymerization reactor of styrene has been addressed. Using a comprehensive dynamic model for PSD and MWD predictions and performing a sensitivity analysis, it has been revealed that free surfactant and chain transfer agent (CTA) concentrations in the reactor are the most suitable candidates for inferential control of PSD and MWD, respectively. To control concentrations of these species in the reactor, their inlet feed flow rates are used as manipulated variables. It is assumed that the concentration of CTA is measured infrequently and therefore an open-looped observer, based on the reaction calorimetry, has been designed to estimate the CTA concentration. The infrequent measurements of CTA concentration are used to correct its estimation. As the online measuring of the ionic free surfactant concentration is also difficult, solution conductivity which is a good indication of free surfactant concentration is used for control purposes. Simulation results show that the performance of the proposed control scheme is satisfactory even in the presence of model mismatch. POLYM. ENG. SCI., 50:2306-2320, 2010. [C] 2010 Society of Plastics Engineers, INTRODUCTION Emulsion polymerization is one of the most important processes in polymer industries for producing a wide range of special products such as latex paints and coating, adhesive, synthetic rubber, [...]

A deterministic model based on thediscrete population balanceequation (PBE) is used to examine the precipitation of barium sulfatenanoparticles in nonionic inverse microemulsion systems. It is shownthat coagulation can have a significant effect at low initial reactantsconcentration. The simulation results show that a bimodal particlesize distribution (PSD) observed in experimental analysis reportedin the literature cannot be predicted by neglecting the coagulationeffect. A coagulation kernel is proposed that takes into account theeffect of interparticle forces through the Fuchs’ stabilityratio. The effect of electrolyte concentration on the surfactant headgrouparea is also investigated. It is shown that at lower electrolyte concentration,the nucleation and growth rates increase because of higher interdropletexchange rate. The simulation results show a qualitatively good agreementwith experimental data regarding PSD prediction and dynamic evolutionof mean particle diameter. [ABSTRACT FROM AUTHOR]

As a result of the transformation of inflexible electronic structures into flexible and stretchy devices, wearable electronics now provide great advantages in a variety of fields, including mobile healthcare sensing and monitoring, human-machine interfaces, portable energy storage and harvesting, and more. Because of their enriched surface functionalities, large surface area, and high electrical conductivity, transition metal nitrides and carbides (also known as MXenes) have recently come to be extensively considered as a group of functioning two-dimensional nanomaterials as well as exceptional fundamental elements for forming flexible electronics devices. This Review discusses the most recent advancements that have been made in the field of MXene-enabled flexible electronics for wearable electronics. The emphasis is placed on extensively established nonstructural features in order to highlight some MXene-enabled electrical devices that were constructed on a nanometric scale. These attributes include devices configured in three dimensions: printed materials, bioinspired structures, and textile and planar substrates. In addition, sample applications in electromagnetic interference (EMI) shielding, energy, healthcare, and humanoid control of machinery illustrate the exceptional development of these nanodevices. The increasing potential of MXene nanoparticles as a new area in next-generation wearable electronic technologies is projected in this Review. The design challenges associated with these electronic devices are also discussed, and possible solutions are presented., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)