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Nanoparticles are extensively used in industrial products or as food additives. However, despite their contribution to improving our quality of life, concerns have been raised regarding their potential impact on occupational and public health. To speed up research assessing nanoparticle-related hazards, this study was undertaken to identify early markers of harmful effects on the lungs. Female Sprague Dawley rats were either exposed to crystalline silica DQ-12 with instillation, or to titanium dioxide P25, carbon black Printex-90, or multi-walled carbon nanotube Mitsui-7 with nose-only inhalation. Tissues were collected at three post-exposure time points to assess short- and long-term effects. All particles induced lung inflammation. Histopathological and biochemical analyses revealed phospholipid accumulation, lipoproteinosis, and interstitial thickening with collagen deposition after exposure to DQ-12. Exposure to the highest dose of Printex-90 and Mitsui-7, but not P25, induced some phospholipid accumulation. Comparable histopathological changes were observed following exposure to P25, Printex-90, and Mitsui-7. Comparison of overall gene expression profiles identified 15 potential early markers of adverse lung outcomes induced by spherical particles. With Mitsui-7, a distinct gene expression signature was observed, suggesting that carbon nanotubes trigger different toxicity mechanisms to spherical particles. [ABSTRACT FROM AUTHOR]

A preparation method of nanocomposites based on poly (3-octylthiophene-2,5-diyl) (POT) and carbon black (CB) as the transducer of an all-solid potassium ion selective electrode is proposed. POT is used as the dispersant of CB, and the obtained nanocomposites have unique characteristics, including high conductivity, high capacitance and high stability. The potassium ion selective electrode based on POT and CB was characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and chronopotentiometry. The results showed that the detection limit of potassium ions was 10−6.2 M, and the slope was 57.6 ± 0.8 mV/façade. The water layer test and anti-interference test show that the electrode has high hydrophobicity, the static contact angle reaches 139.7° and is not easily affected by light, O2 and CO2. [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]

In the last two decades, wearable piezoresistive physical sensors have attracted tremendous attention due to their broad applications in individual health-monitoring, human–machine interfaces, robotics, sports and therapeutics. Many different nanostructured materials, including nanowires, nanoparticles, nanoribbons, carbon black, carbon nanotubes and graphene, have been explored to construct stretchable piezoresistive sensors on an elastomer substrate. Thanks to its unique two-dimensional geometry, lightweight, flexibility, semi-transparency and outstanding transport and mechanical properties, graphene and its derivatives in particular are considered among the most suitable candidates as wearable sensors. This paper reviews various design strategies established for fabricating flexible, wearable sensors using graphene. The current state-of-the-art developments are discussed of flexible sensors made of 1D fibrous, 2D planar and 3D cellular interconnected graphene architectures for detecting physiological strains, tactile pressures and temperatures. The working mechanisms along with existing applications of flexible sensors are presented. The challenges these sensors are currently facing and potential opportunities for novel applications are revealed to offer new insights into future prospects in this field. [ABSTRACT FROM AUTHOR]

Abstract: The increased production of nanoparticles is providing increased investigation of the biological influences they induce. Studies of the biological influences of nanocarbons are also increasing. Some nanocarbons, such as carbon black, fullerene and carbon nanotubes, induce oxidative stress on cultured cells. On the other hand, there are few reports about the cellular influences of nanodiamond. A risk assessment based on accurate evaluation of biological influences is essential for the effective utilization of nanodiamond. In the present study, we prepared nanodiamond culture medium dispersions kept stable for the experimental period and examined their cellular influences. The secondary particle size of nanodiamond in the medium dispersion was 41–103nm. The dispersion was exposed to HaCaT and A549 cells at concentrations of 1.0, 0.1 and 0.01mg/mL for 6 and 24h. After that, mitochondrial activity, apoptosis, intracellular reactive oxygen level, lipid peroxidation, colony formation and cellular uptake were examined. Transmission electron microscopic observations showed cellular uptake of nanodiamond. Slight apoptosis and inhibition of colony formation were shown in the HaCaT cells at a concentration of 1.0mg/mL. Nanodiamond did not influence cell viability, cell membrane injury, or intracellular oxidative stress. Our results suggest that the cellular influences of nanodiamond are smaller than other nanocarbons. [Copyright &y& Elsevier]

Epoxy nanocomposites including multi-wall carbon nanotubes (MWCNT) and carbon black (CB) were produced and investigated by means of electrical conductivity measurements and microscopical analysis. Varying the weight fraction of the nanoparticles, electrical percolation behaviour was studied. Due to synergistic effects in network formation and in charge transport the inclusion of both MWCNT and CB in the epoxy matrix leads to an identical electrical behaviour of this ternary nanocomposite system compared to the binary MWCNT-epoxy system. For both types of nanocomposites an electrical percolation threshold of around 0.025 wt% and 0.03 wt% was observed. Conversely, the binary CB nanocomposites exhibit a three-times higher percolation threshold of about 0.085 wt%. The difference between the binary MWCNT-epoxy and the ternary CB/MWCNT-epoxy in electrical conductivity at high filler concentrations (e.g. 0.5 wt%) turns out to be less than expected. Thus, a considerable amount of MWCNTs can be replaced by CB without changing the electrical properties. [ABSTRACT FROM AUTHOR]