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Waste tire rubber has become a severe environmental issue, which calls for a green method to recycle this rubber. Microwave thermolysis serves as an ideal recycling process for used tires. By surveying the dielectric characteristics from 25 to 700 °C under microwave frequencies of 915 and 2466 MHz, the microwave absorption ability of waste tire rubbers was studied. At temperatures below 350 °C, the dielectric characteristics were relatively steady. Both the loss factor and relative dielectric constant (DC) increased sharply with the rise in temperature. The reason for this is the release of volatile substances, which increases the electrical conductivity. The performance of microwave absorption of tire rubber during thermolysis, and thus the efficiency of microwave tire rubber thermolysis, can be largely impacted by the specimen dimension. The calculation of the reflection loss (RL) of the tire rubber specimens suggests that when the waste tire rubber is 5 mm thick, the highest microwave absorption can be achieved at 915 MHz and 592.1 °C, with RL of −17.30 dB. The product after microwave pyrolysis of waste tire rubber comprises 35% carbon black, 40% oil, and 25% gas. Based on this investigation of the optimal condition of microwave absorption, a proper microwave pyrolysis recycling system was designed for waste tire. This system is efficient at recycling the waste tire rubber into valuable carbon black, oil, and gas products.

Rat renal tubular epithelial cell (RTEC) cultured with high glucose has been used to observe the protective effect of Ginkgo biloba extract (GBE) against diabetic nephropathy (DN). The compounds in GBE binding with cell membrane or entering into cell are still unknown, which may be potential bioactive components. In this paper, a powerful method for screening and analyzing the potential bioactive components from GBE was developed using cell extraction coupled with high performance liquid chromatography tandem mass spectrometry (LC-MS/MS). 8 prototype compounds and 5 metabolites were obtained, among which 6 prototype compounds and 1 metabolite were identified or tentatively characterized as rutin, bilobalide, ginkgolide B, ginkgolide C, genkwanin, apigenin and diosmetin by comparing their retention times and MS spectra with those of authentic standards or literature data. The 6 prototype compounds were further quantitatively analyzed using electrospray ionization in negative mode multiple reaction monitoring (MRM). The results showed that high glucose changed the Tmax, MRT(0-t), Cmax and AUC(0-t) of all observed compounds and decreased the t1/2 of genkwanin and apigenin, significantly. The overall findings indicate that 8 prototype compounds may be the potential bioactive components of GBE with preventive effect against DN and the method of RTEC extraction coupled with LC-MS/MS technology screening method we developed is a feasible, rapid, and useful tool for screening and analyzing potential bioactive components.