A method for molecularly imprinted SPE of the melamine from environmental water samples was investigated. Cyromazine-imprinted polymers were synthesized in water-methanol systems for the selective extraction of melamine from aqueous samples, followed by HPLC analysis. Molecular recognition properties and binding capability to melamine were evaluated by adsorption test and Scatchard analysis, which showed the dissociation constant (KD) and the maximum binding quantity (Qmax) were 0.032 micromol/L and 4.77 micromol/g for high affinity binding site, and 0.26 micromol/L and 19.10 micromol/g for lower affinity binding site, respectively. Under the optimum extraction protocol, the method can be successfully applied to selectively extract and enrich melamine in environmental water. The linearity was ranged from 0.500 to 100.0 ng/mL (r > 0.999) in tap water, lake water, and seawater analysis. When 50 mL of the water samples loaded, the LODs of the method were ca. 0.1 ng/mL, and the LOQs were ca. 0.5 ng/mL. The mean recoveries of melamine from blank water samples spiked at 0.5, 5.0, and 50 ng/mL were more than 86.3%, with the RSD less than 8.8%.

Mangiferin ameliorated the progression of AH by regulating the metabolic network associated with damage-associated molecular patterns, lipid metabolic disorder and mitochondrial dysfunction in AH rats.

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To further improve the ablation and thermal properties of silicon rubber composite materials, the 3, 13-divinyloctaphenyl double-decker polyhedral oligomeric silsesquioxane (DV-DDSQ) modified additional vinyl-terminated polydimethylsiloxane (VPDMS) was prepared, and the effect of high silica fiber reinforcement on the ablation properties of VPDMS was investigated. The results show that when 0.8phr DV-DDSQ was added, the mass residual rate at 800 C of the composites increased from 40.6% to 51.0%. The linear ablation rate (LAR) as well as mass ablation rate (MAR) of the composites of the DV-DDSQ modified VPDMS, the high silica fiber reinforced VPDMS composite (HSF/VPDMS composite) and the high silica fiber reinforced DV-DDSQ modified VPDMS composite (HSF/DV-DDSQ-VPDMS composite) decreased dramatically compared with raw VPDMS, and it was 16.36%, 35.69%, and 37.17% bring down for LAR and 5.34%, 14.60% and 25.59% for MAR, respectively. The tensile strength and hardness of the DV-DDSQ modified composites increased by 9.52% and 14.13%, respectively, while the elongation at break decreased by 5.99%, compared with the raw VPDMS.

Mangiferin (MG) is an active component in natural medicines, and various studies have been reported on pharmacological effects, but the low solubility and bioavailability of MG limit its wide application. The aim of the present study was to investigate the pharmacokinetic profiles of mangiferin (MG) and mangiferin monosodium salt (MG-Na) in rat plasma by UPLC-MS/MS, which were then compared between the two groups. An appropriate high sensitivity and selectivity ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was applied to the comparison of plasma pharmacokinetics in MG and MG-Na using carbamazepine as internal standard (IS). These results showed that there were statistically significant differences in the pharmacokinetic parameters between MG and MG-Na after a single oral administration at 100 mg/kg. When compared with pharmacokinetic parameters of MG, the AUC(0-t), AUC(0–∞), Cmax,K10, and Ka of MG-Na were increased by 5.6-, 5.7-, 20.8-, 8-, and 83.6-fold, while the Tmax and CL/F were decreased by 4- and 5.7-fold (P<0.001), respectively. t1/2 value showed an increasing trend, but was statistically significant between the two groups. Moreover, the AUC value in the MG-Na group was significantly increased and the relative bioavailability was calculated to be 570% when compared with that of the MG group. These results suggested that the salification reaction of MG can effectively enhance gastrointestinal absorption and relative bioavailability by improving solubility and membrane permeability.

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Bifunctional reactive polyhedral oligomeric silsesquioxane (POSS) of 3, 13‐divinyl octyphenyl silsesquioxane (DV‐DDSQ) and 3, 13‐dihydro octyphenyl silsesquioxane (DH‐DDSQ) were used as additive to modify ethylene‐propylene‐diene rubber (EPDM), and double vinyl groups or active hydrogen groups of bifunctional reactive POSS (brPOSS) underwent a cross‐linking reaction with the active hydrogen groups and double bonds of EPDM, to investigate the effect of brPOSS regulating functional reaction group on the properties of EPDM. Crosslinking density, mechanical properties, thermal stability and ablation performance of brPOSS modified EPDM were investigated, and the pyrolysis behavior and surface structure of modified EPDM was analyzed by X‐ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Furthermore, the ablation performance of brPOSS modified insulation based on EPDM was investigated. The results showed that the tensile strength of EPDM/DV‐DDSQ and EPDM/DH‐DDSQ increased by 35.8% and 55.3% respectively compared with EPDM; the tear strength increased by 6.4% and 5% than that of EPDM. Moreover, the 5% initial thermal decomposition temperature based on thermogravimetric analysis (TGA) and mass (or linear) ablation rate ablative performance of brPOSS modified EPDM were optimized to a certain extent, and the ablative performance of brPOSS modified insulation based on is significantly improved, the mass ablation rate of DV‐DDSQ/insulation and DH‐DDSQ/insulation decreased by 35.4% and 41.6% respectively, and linear ablation rate decreased by 38.2% and 39.4% respectively.