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Herein, radio frequency (RF) Joule heating is used to trigger dynamic covalent bond exchange in a furan‐maleimide Diels–Alder polymer (DAP). Prior work shows that carbon susceptors can be incorporated into materials and undergo Joule heating when exposed to an electric field. Herein, carbon nanotubes (CNTs) are added to the DAP to make the material responsive to RF fields, and to enable selective, noncontact healing behavior of DAP after electric field exposure. After healing, mechanical testing is conducted to compare the tensile strength and toughness of the healed samples with the mechanical properties of the original, undamaged samples. A 96.2% recovery in tensile strength and an 83.2% recovery in toughness are observed. Also, RF heating of DAP/CNT enables repeated bonding and debonding of the material, allowing for adhesion and deadhesion on demand. [ABSTRACT FROM AUTHOR]

Sodium borohydride (NaBH4), with a high theoretical hydrogen content (10.8 wt%) and safe characteristics, has been widely employed to produce hydrogen based on hydrolysis reactions. In this work, a porous titanium oxide cage (PTOC) has been synthesized by a one-step hydrothermal method using NH2-MIL-125 as the template and L-alanine as the coordination agent. Due to the evenly distributed PtNi alloy particles with more catalytically active sites, and the synergistic effect between the PTOC and PtNi alloy particles, the PtNi/PTOC catalyst presents a high hydrogen generation rate (10,164.3 mL∙min−1∙g−1) and low activation energy (28.7 kJ∙mol−1). Furthermore, the robust porous structure of PTOC effectively suppresses the agglomeration issue; thus, the PtNi/PTOC catalyst retains 87.8% of the initial catalytic activity after eight cycles. These results indicate that the PtNi/PTOC catalyst has broad applications for the hydrolysis of borohydride. [ABSTRACT FROM AUTHOR]

Conductive elastomer composites (CECs) with segregated filler networks display a combination of good mechanical properties and electrical conductivity, enabling potential applications in flexible and stretchable electronics. However, it is challenging to achieve high strain sensitivity and to retain good elasticity. Here, hybrid fillers of carbon nanostructures (CNS, also known as branched carbon nanotubes) and graphene are used to achieve high strain sensitivity of thermoplastic polyurethane (TPU)‐based CECs without decreasing elasticity and electrical conductivity. By changing the graphene type, namely, single layer graphene nanosheet (GNS) and graphene nanoplatelets (GNP), mechanical properties and strain–sensing performances of the CECs can be modulated effectively at proper hybrid filler compositions. Due to the effect of graphene morphology, the TPU/CNS–GNP system has higher strain sensitivity by comparison with the TPU/CNS–GNS system. These CECs demonstrate potential applications as flexible/wearable electronics in body joint bending and flexible switches and resistors for current regulation. [ABSTRACT FROM AUTHOR]

Abstract Background Herb mixtures are widely used as an alternative to hormonal therapy in China for treatment of the menopausal syndrome. However, composition of these herb mixtures are complex and their working mechanism is often unknown. This study investigated the effect of Tiáo-Gēng-Tāng (TG-decoction), a Chinese herbal mixture extract, in balancing female hormones, regulating expression of estrogen receptors (ERs), and preventing aging-related tissue damage. Methods Ovariectomized 5-month-old female rats were used to model menopause and treated with either TG-decoction or conjugated estrogen for 8 weeks. Estradiol (E2), luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were measured in serum and in the hypothalamus. Hypothalamic expression of estrogen receptor (ER) alpha and beta were studied by real-time PCR and western blotting. Total antioxidant capacity (T-AOC), oxidation indicator superoxide dismutase (SOD) activity and tissue damage parameter malondialdehyde (MDA) were measured using standard assays. Aging-related ultrastructural alterations in mitochondria were studied in all animals by transmission electron microscopy. Results TG-decoction-treatment elevated E2 and lowered FSH in serum of ovariectomized rats. The potency and efficacy of TG-decoction on the hypothalamus was generally weaker than that of conjugated estrogens. However, TG-decoction was superior in upregulating expression of ERα and β. TG-decoction increased hypothalamic SOD and T-AOC levels and decreased MDAlevels and mitochondrial damage in hypothalamic neurons. Conclusions TG-decoction balances female hormones similarly to conjugated estrogens but less effectively. However, it is superior in up regulating ERα and β and exhibits antioxidative antiaging activities. Whilst it shares similar effects with estrogen, TG-decoction also seems to have distinctive and more complex functions and activities.

As an alternative of single filler system, hybrid fillers system is beneficial for the fabrication of elastomer‐based piezoresistive strain sensors with high strain sensitivity for structural health monitoring and human motion detection. However, a comprehensive understanding for the effect of the secondary filler dimensionality on piezoresistive strain sensor sensitivity by hybrid carbon nanofillers strategy is missing. Here, we report a comparative study about the effect of branched carbon nanostructures (CNS, three‐dimensional, 3D) combined with carbon black (CB, 0D) or carbon nanotubes (CNT, 1D) on the piezoresistive behavior of thermoplastic polyurethane (TPU)‐based composites. At either the same total filler content or similar electrical resistivity, using CNS‐CB hybrid is more efficient than using CNS alone or CNS‐CNT hybrid for improving piezoresistive sensitivity of the TPU composites. For instance, the composite 1.5CNS‐1CB has a gauge factor (GF) of 21 and 99 at strain ε = 50 and 100%, respectively, while the composites 2.5CNS and 1.5CNS‐1CNT have GF values of 4.3 and 9.1 at strain ε = 50% and 14 and 20 at strain ε = 100%, respectively. Besides, the TPU composite with CNS‐CB shows a larger response to finger bending (50° on an index finger) by comparison with that contains only CNS, indicating potential applications for human motion detection. This study introduces a facile way to fabricate strain‐sensitive sensors aimed at strain of 50%–100%, strengthening understanding the selection of hybrid carbon nanofillers with different dimensionalities to optimize piezoresistive sensor design. [ABSTRACT FROM AUTHOR]