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Abstract: Nd2SiO5 ceramics were synthesized and their microwave dielectric properties were investigated. The hexagonal Nd4Si3O12 second phase disappeared and the pure monoclinic Nd2SiO5 phase could be obtained when the molar ratio of Nd2O3/SiO2 was 1:1.05 at 1450°C. The relative density of Nd2SiO5 ceramics increased with increasing temperature. The Nd2SiO5 ceramics sintered at 1500°C exhibited microwave dielectric properties: a dielectric constant (ε r) of 7.94, a quality factor (Q × f) of 38 800GHz and a temperature coefficient of resonant frequency (τ f) of −53ppm/°C. High resonant frequency led to a low dielectric constant and low Q × f value. Nd2SiO5 ceramics have a wide sintering temperature region. They are promising candidate materials for microwave passive components. [Copyright &y& Elsevier]

A solution-based “hot-injection” approach was developed to synthesize amorphous carbon-decorated and graphene-anchored hollow Co 9 S 8 nanoparticles as anode material for Li ion battery application. Such a rationally designed dually-protected structure could effectively accommodate the volume expansion of Co 9 S 8 nanoparticles during Li-cycling. As a result, as-synthesized nanocomposites could be successfully operated under ultrawide temperature window of −20 °C–70 °C, rendering excellent electrochemical performances, i.e., remarkable reversible capacities of 910 mA h g −1 after 100 cycles (at 500 mA g −1 ) and 622 mA h g −1 after 200 cycles (at 1000 mA g −1 ) at 70 °C. These attributes enable three-dimensional structured Co 9 S 8 nanoparticles to be promising anode materials of advanced Li-ion batteries for large-power applications such as electric vehicles under extreme temperature environments. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (rGO)-encapsulated MnGeO 3 microspheres have been yielded via a facile, scalable and environmentally friendly route. Hydrothermal method was utilized to recrystallize MnGeO 3 particles and form rGO encapsulation. Such rationally designed rGO-encapsulated MnGeO 3 microspheres afforded excellent electrochemical performances, i.e. high first discharge capacity of 1364 mAh g −1 and charge capacity of 810.8 mAh g −1 , and reversible capacity of 624.6 mAh g −1 after 50 cycles at a current density of 200 mA g −1 when they were employed as anode materials for Li ion batteries. These advantageous attributes make rGO-encapsulated MnGeO 3 microspheres the potential anode materials for Li-ion batteries. [ABSTRACT FROM AUTHOR]

Abstract: SnO2-doped CaSiO3 ceramics were successfully synthesized by a solid-state method. Effects of different SnO2 additions on the sintering behavior, microstructure and dielectric properties of Ca(Sn1−x Si x )O3 (x=0.5–1.0) ceramics have been investigated. SnO2 improved the densification process and expanded the sintering temperature range effectively. Moreover, Sn4+ substituting for Si4+ sites leads to the emergence of Ca3SnSi2O9 phase, which has a positive effect on the dielectric properties of CaO–SiO2–SnO2 materials, especially the Qf value. The Ca(Sn0.1Si0.9)O3 ceramics sintered at 1375°C possessed good microwave dielectric properties: ε r =7.92, Qf =58,000GHz and τ f =−42ppm/°C. The Ca(Sn0.4Si0.6)O3 ceramics sintered at 1450°C also exhibited good microwave dielectric properties of ε r=9.27, Qf=63,000GHz, and τ f =−52ppm/°C. Thus, they are promising candidate materials for millimeter-wave devices. [Copyright &y& Elsevier]

The poor Uv stability and weak interfacial adhesion are considered as the bottleneck problems for further application of aramid fiber. Herein, a new strategy, Fe 3+ coordination, was reported for aramid fiber to simultaneous improve its Uv resistance and composite interfacial shear strength. Fe 3+ was introduced onto aramid fiber by coordinating with benzimidazole unit of fiber structure. It can reach a doping capacity of as high as 1516ug/g fiber, and the fiber surface is saturatedly covered with Fe 3+ . The chemical structure of Fe 3+ -benzimidazole brings about strong metal-enhanced fluorescence emission effect, which, in turn, greatly raises its Uv stability. Owing to the Fe 3+ coordination, the tensile strength of Fe-coordinated fiber could preserve as high as 96% after Uv irradiation, compared with 73% of untreated fiber. Meanwhile, the introduction of Fe 3+ improves the surface polarity of aramid fiber and consequently leads to the increase of the composite interfacial shear strength by 39%. It is believed that the Fe-coordinated fiber integrates the advantages of easy production, cost-effective and increased Uv stability, as well as high composite interfacial adhesion, and can be used as promising enhancement for the advanced composite material in harsh environment. [ABSTRACT FROM AUTHOR]

Graphene-covered and carbon-encapsulated CoSO 4 nanoparticles (a-C@CoSO 4 @GNs) were first prepared by a facile solution-phase route followed by heat treatment. Subsequently, a-C@CoSO 4 @GNs nanoparticles were utilized as anode materials of Li ion batteries. Such a rationally designed three-dimensional nanostructure could effectively accommodate the volume expansion of CoSO 4 particles during Li-cycling. As a consequence, a-C@CoSO 4 @GNs have delivered remarkable electrochemical performances, i.e., high first discharge capacity (994 mA h g −1 ), prominent cyclic performance of 662.7 mA h g −1 at a current density of 200 mA g −1 and excellent large-current capacity of 497 mA h g −1 at a current density of 1.5 A g −1 after 50 cycles due to catalytically reduced mechanism. More importantly, a-C@CoSO 4 @GNs electrodes possessed outstanding low/high temperature properties, i.e., reversible capacity of 130 mA h g −1 at −20 °C and 1362 mA h g −1 at 60 °C at a current density of 200 mA g −1 . These advantageous attributes make inexpensive, easily available, widespread and non-toxic CoSO 4 promising candidate as anode materials for high-performance lithium-ion batteries under extremely operational environments. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study is to observe the synergistically enhanced percutaneous penetration and skin analgesia of tetracaine gel containing menthol and ethanol through experimental and clinical studies. Four anesthetic gels containing 4% tetracaine in carbomer vehicle named T-gel (containing no menthol or ethanol), 5%M/T-gel (containing 5% menthol), 70%E/T-gel (containing 70% ethanol, an optimal concentration for antiseptic), and 5%M+70%E/T-gel (containing both 5% menthol and 70% ethanol), respectively, were fabricated. The in vitro mouse skin permeation was investigated using a Franz diffusion cell. The mouse skin morphology was examined by a scanning electron microscope. The in vivo skin analgesic effect in mice was evaluated using the von Frey tests. To determine the efficacy of tetracaine gels for managing the pain in human volunteers, a paralleled, double-blinded, placebo-controlled, randomized controlled trial design combined with verbal pain scores (VPS) was performed. The combination of menthol and ethanol (5%M+70%E/T-gel) conferred significantly higher tetracaine diffusion across full-thickness mouse skin than 5%M/T-gel, 70%E/T-gel, and T-gel. The ultra structure changes of mouse skin stratum corneum treated with 5%M+70%E/T-gel were more marked compared with those of any other tetracaine gel. von Frey tests in mice showed a synergistically enhanced effect of menthol and ethanol on the analgesia of tetracaine gel. The mean VPS were significantly lower for volunteers treated with 5%M+70%E/T-gel than those receiving other gels or the EMLA cream. 5%M+70%E/T-gel possessed the shortest anesthesia onset time, the longest anesthesia duration and the strongest anesthesia efficacy. Seventy percent ethanol in 5%M+70%E/T-gel not only improved the analgesic efficacy of the tetracaine gel through synergistically enhanced percutaneous permeation with menthol but also served as an antiseptic agent keeping drug application site from infection. 5%M+70%E/T-gel is a potential topical anesthesia preparation for clinical use. [Copyright &y& Elsevier]