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Glycyrrhizic acid (GA) and Sirtuin3 (Sirt3) were both found to be involved in epilepsy (EP), but their interaction was rarely studied. Herein, we aim to investigate the underlying mechanism of GA with the interaction of Sirt3 in juvenile EP rats. The EP model in juvenile rats was established by lithium chloride-pilocarpine and treated with different concentrations of GA, GA + DMSO or GA + 3-TYP [a selective inhibitor of Sirtuin3 (Sirt3)]. The expression of Sirt3, mitochondrial autophagy-related genes (C-III core 1, COX IV, LC3-I, LC3-II), apoptosis-related genes (Bcl-2, Bax, Caspase-3), glutathione (GSH), superoxide dismutase (SOD), malondialchehyche (MDA) and reactive oxygen species (ROS) as well as mitochondrial membrane potential were subsequently detected. The juvenile EP rats treated with GA showed increased level of C-III core 1 and COX IV, increased LC3-I/LC3-II, GSH and SOD, decreased MDA, increased expression of Sirt3, and Bcl-2, and decreased expression of Bax and Caspase-3. However, inhibition of Sirt3 caused reverse results. Collectively, GA could alleviate hippocampal pathological damage, promote mitochondrial autophagy and reduce oxidative stress in juvenile EP rats through activation of Sirt3. Understanding of these mechanisms may allow devising of novel therapeutics for pediatric EP.

In this article, the facile synthesis of sea urchin-shaped LiFePO4 nanoparticles by thermal decomposition of metal-surfactant complexes and application of these nanoparticles as a cathode in lithium ion secondary batteries is demonstrated. The advantages of this work are a facile method to synthesize interesting LiFePO4 nanostructures and its synthetic mechanism. Accordingly, the morphology of LiFePO4 particles could be regulated by the injection of oleylamine, with other surfactants and phosphoric acid. This injection step was critical to tailor the morphology of LiFePO4 particles, converting them from nanosphere shapes to diverse types of urchin-shaped nanoparticles. Electron microscopy analysis showed that the overall dimension of the urchin-shaped LiFePO4 particles varied from 300 nm to 2 μm. A closer observation revealed that numerous thin nanorods ranging from 5 to 20 nm in diameter were attached to the nanoparticles. The hierarchical nanostructure of these urchin-shaped LiFePO4 particles mitigated the low tap density problem. In addition, the nanorods less than 20 nm attached to the edge of urchin-shaped nanoparticles significantly increased the pathways for electronic transport.

Natural rubber (NR) has excellent mechanical properties due to its unique molecular chain structure. In previous studies, the signal of the cis- and trans-isoprene units was deduced by 13C-NMR spectrum of the low molecular weight fraction of NR. In this study, through investigating the 1H-NMR spectra of ribbed smoked sheet 1 (RSS-1) and standard Chinese rubber whole fraction (SCR-WF), and Eucommia ulmoides gum (EUG), trans-1,4-polyisoprene (TPI), found that the methyl-proton in the cis- and trans-isoprene units in 1H-NMR spectra of NR showed signals at 1.61 and 1.53 ppm, respectively. Further, the content of trans-structure in the molecular chain of NR of different producing areas was calculated. The results show that the content of trans-structure in the molecular chain structure of RSS-1 and SCR-WF were 1.500 and 1.054%, respectively.

This work studied possibilities of using lanthanum stearate (LaSt) as an antioxidant in epoxidized natural rubber containing 25 mol.% expoxidation (ENR25) compounds. For comparison purposes, two commercial antioxidant 4010NA and MB were also used. The influence of LaSt, antioxidant 4010NA and MB on cure characteristics, mechanical properties, crosslink density, hot air aging and thermo-oxidative degradation were studied. The results indicated that the incorporation of LaSt and antioxidants could accelerate the vulcanization of ENR. The ENR vulcanizates with antioxidant MB had better mechanical properties than 4010NA and LaSt. Compared with antioxidant 4010NA and MB, the ENR25 vulcanizates with the addition of LaSt exhibited the best hot air aging resistance and thermo-oxidative stability.

The effect of neodymium stearate (NdSt) synthesized by saponification method on thermal degradation and thermo-oxidative degradation of expoxidized natural rubber with 25 mol.% epoxidation (ENR25) was investigated by thermogravimetric analysis (TGA), and the structure of ENR25 vulcanized with NdSt after thermo-oxidative decomposition was characterized using Fourier transform infared spectroscopy-attenuated total-reflectance (FTIR-ATR). The thermal degradation kinetic parameters of ENR25 with different loadings of NdSt were determined by Coats-Redfern method. The results showed that the thermal degradation of ENR25 in nitrogen was a one-step reaction regardless of NdSt content, whereas the thermo-oxidative degradation was a multiple-step reaction. The thermal and thermo-oxidative stability of the ENR25 vulcanizates with the addition of NdSt was higher than that of pure ENR25 vulcanizates. The ENR25 vulcanizates with the incorporation of 1 phr (per hundred parts of rubber) NdSt imparted the highest activation energy (E) of thermal and thermo-oxidative degradation. This could be attributed to the many unoccupied orbits in rare earth Nd, which could capture the free radicals and make the epoxide groups stable in the process of thermal and thermo-oxidative degradation for ENR25.

We investigated the effect of ionic liquid molecules (ILMs) in hybrid quantum dot-organic solar cells (HyQD-OSCs). The insertion of an ILM layer between PbS and phenyl-C61-butyric acid methyl ester (PCBM) can shift the band edge of PCBM closer to the vacuum level of PbS due to spontaneous dipole polarization. Because of this new architecture, improvements in device performance were achieved, including increases in open-circuit voltage (VOC, from 0.41 V to 0.49 V), fill factor (FF, from 0.48 to 0.59), and power conversion efficiency (PCE, from 1.62% to 2.21%), compared to reference devices under AM 1.5G illumination at 100 mW cm(-2). We observed that treatment of the PbS layer with ILMs causes a significant increase in work function from 3.58 eV to 3.93 eV. Furthermore, the ILMs layer minimizes the contact resistance between PbS and PCBM due to the improved compatibility between the two layers, confirmed as a decrease in charge transfer resistance, as measured by electrical impedance spectroscopy.

Natural rubber–epoxidized natural rubber–silica composites were prepared by the wet masterbatch technique and the traditional dry mixing method. Performances of the composites based on different preparation methods were investigated with a moving die rheometer, an electronic universal testing machine, a dynamic mechanical analyzer, a nuclear magnetic resonance crosslink density analyzer, a rubber processing analyzer (RPA), a scanning electron microscope (SEM), and a transmission electron microscope (TEM). The RPA, SEM, and TEM analyses indicated that silica has better dispersion, lower filler–filler interaction, and better filler–rubber interaction in compounds based on the wet masterbatch technique, leading to improvements in mechanical strength and the dynamic mechanical and compression properties of the composites. It also indicates that composites prepared by the wet masterbatch technique have shorter scorch time, faster curing velocity, and higher crosslink density. The composites prepared by the wet materbatch technique also have lower rolling resistance, which is an important property for their use as a green material for the tire industry.

The effect of neodymium stearate (NdSt) on cure and mechanical properties of expoxidized natural rubber with 25 mol.% epoxidation (ENR25) was studied in the concentration range of 0 to 2 phr, and the relationship between structure and mechanical properties of ENR25 vulcanizates was also discussed. Neodymium sterate was synthesized by saponification of stearic acid with newly formed rare earth hydroxide in water medium, and the structure of NdSt was investigated by Fourier transform infrared spectroscopy (FTIR). Crosslinking density of vulcanized natural rubber was studied by equilibrium swelling method. The results indicated that the interaction force between carboxylic ion of NdSt prepared in the lab and Nd ion was mainly ionic bond through FTIR analysis. NdSt could accelerate the vulcanization of ENR25 and influence the network structure of ENR25 vulcanizates. The incorporation of 1 phr NdSt for ENR25 vulcanizates showed the optimal aging resistance.