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Tryptophan, an essential amino acid playing a pivotal role in various biological processes, stands as a focal point in our investigation. In this study, we introduce a groundbreaking electrochemical sensor that integrates a nanocomposite comprising carbon black (CB) and zinc oxide nanoparticles (ZnO-NPs) for the selective detection of L-tryptophan (Trp). The synthesis of ZnO-NPs, accomplished through the sol-gel technique, was meticulously characterized using XRD, FTIR, and UV-visible methods to unveil their structural and optical properties. The construction of the sensing electrode involved the deposition of a CB/ZnO-NP nanocomposite onto a glassy carbon electrode (GCE) utilizing the drop-coating method. Rigorous evaluation and analysis of the modified glassy carbon electrode were carried out through scanning electron microscopy (SEM), cyclic voltammetry (CV), and differential pulse voltammetry (DPV). The resulting CB/ZnO-NPs/GCE electrode exhibited an augmented surface area and outstanding electrocatalytic activity. Significantly, the CB/ZnO-NP sensor displayed remarkable analytical performance for tryptophan detection over an extensive concentration range from 0.01 to 100 µmol.L−1, featuring a low detection limit of 0.017 µmol.L−1. Moreover, the proposed electrochemical sensor exhibited notable selectivity, specifically targeting tryptophan, emphasizing its potential for diverse analytical applications. This work not only expands our understanding of tryptophan detection but also offers a highly sensitive and selective tool with broad applications in biomedical and environmental fields, underscoring the significance of this innovative sensor in advancing analytical methodologies. [ABSTRACT FROM AUTHOR]

The present study is devoted to investigating the mechanical characteristics of a novel natural rubber (NR)-based elastomer nanocomposite reinforced with carbon black and alumina nanoparticles acting as partial and primary reinforcements, respectively. Before conducting various mechanical tests on the specimens, the vulcanization properties of this elastomer nanocomposite was surveyed. It is demonstrated that adding the alumina nanoparticles to the NR-based elastomer matrix can significantly reduce the cure time and improve the quality of the vulcanizates. Then, the influence of alumina nanoparticles on the modulus, tensile strength, elongation at break, and energy absorption capacity of the elastomer nanocomposite were assessed, and the ideal nanoparticles' weight percentage was determined to be 10%. This is supported by calculating the Reinforcing Efficiency Parameter (REP), indicating that the elastomer nanocomposite with 10% alumina has the best reinforcing efficiency in tensile properties. Also, using the Split Hopkinson Pressure Bar (SHPB), it was found that the material is exceptionally strain-rate sensitive, and the specimens exhibited much higher values of stiffness and energy absorption under high strain-rate loading. It is inferred from the results that the elastomer nanocomposite reinforced with the optimal amount of alumina nanoparticles can be an excellent candidate for energy absorption applications under high strain-rate loadings. [ABSTRACT FROM AUTHOR]

Hybrid nanocomposites of high‐density polyethylene have been prepared via the melt‐mixing method in the presence of different amounts of graphene nanoplatelets (GNPs) and conductive carbon black (CB). The electrical conductivity, positive temperature coefficient (PTC), and the correlation between crystallinity and electrical conductivity of hybrid nanocomposites are investigated to study the effect of crystallinity on electrical conductivity. The samples are characterized using differential scanning calorimetry (DSC), scanning electron microscopy (SEM), X‐ray diffraction (XRD), and electrical resistivity. SEM micrographs reveal good distribution of CB and GNPs in nanocomposites. According to DSC and XRD results, the crystallinity of samples decreases by the addition of CB and GNP. The electrical conductivity of all the samples increases, whereas in the sample 16% of CB and 1% of GNP electrical conductivity decrease due to GNP acting as a heterogeneous nucleating agent and the numerous incomplete and small crystals formation. The highest electrical conductivity (1.46×10−4 S cm−1) is obtained in the sample high‐density polyethylene (HDPE)/CB18/GNP1, which shows high increment in the PTC curve in the range of 105−120 °C. Also, repeatability and reversibility of PTC in this sample show good potential for use in different applications such as thermistors, temperature sensors, and self‐regulating heaters. [ABSTRACT FROM AUTHOR]

TiC/Al–Cu nanocomposites were fabricated in Al–Ti–C powder systems using carbon black, a mixture of C and carbon nanotubes (C + CNTs), and CNTs via an in-situ method involving combustion synthesis and hot pressing. As the carbon source changed from pure carbon black to the C + CNT mixture and pure CNTs, the size of the TiC nanoparticles decreased gradually. The nanocomposites synthesized based on the C + CNT mixture exhibited the most uniform dispersion of TiC nanoparticles. The 30 vol% TiC/Al–Cu nanocomposite prepared from the C + CNT mixture had the best comprehensive mechanical properties (yield strength (411 MPa), compressive strength (712 MPa), fracture strain (17.2%), hardness (206.8 HV), and wear resistance under the experimental conditions due to having the most uniformly dispersed TiC nanoparticles. The wear mechanism was a combination of plastic deformation, abrasion, and adhesion. This method may be a low-cost and convenient means to control the sizes of in-situ TiC nanoparticles and prepare high-performance TiC/Al–Cu nanocomposites. [ABSTRACT FROM AUTHOR]

Hydrogel nanocomposites have been enthusiastically researched as promising candidates with cost-effectiveness and sustainability for solar steam generation and flexible electronics. Based on conductivity derived from salt ions and superior photo-vapor conversion of photothermal nanoparticles, hydrogel nanocomposites hold great potentials for ionotronics and desalination. Here, we report a mechanically robust and multifunctional gel-nacre nanocomposite based on carbon black (CB) nanoparticles strategically embedded in gel-nacre matrix, a physical crosslinked hydrogel reinforced via freeze–thaw and salting out with microphase separation structures. The CB nanoparticles play double roles of acting as nano-crosslinks and providing photothermal conversion capability, coupling gel-nacre matrix with shrinking tendency in saline, contributing to synergistical reinforcement of mechanical performances under saline conditions. The consequent CB@gel-nacre nanocomposite achieves comprehensive mechanical advantages (large strength, high toughness, ductility, and rapid self-recoverability), excellent electrical properties (good conductivity, high sensitivity, fast strain response) as well as photothermal conversion capability. Such versatile gel-nacre nanocomposite provides new opportunities for flexible devices in various scenarios such as ionotronics and desalination. [ABSTRACT FROM AUTHOR]