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HP-Innowax capillary column was selected and the content of menthol, triacetin and nicotine in mint cigarette filter was determined by gas chromatography with anhydrous ethanol as extraction solvent. The results showed that: The linear relationship was good among menthol, triacetic acid and nicotine in the concentration range of 0. 30 ~4. 80 g ⋅ L-1, 0. 30 ~4. 80 g ⋅ L-1 and 0. 01 ~0. 16 g ⋅ L-1, respectively, the limit of quantification was 14.4 µg ⋅ branch-1,29. 8 µg ⋅ branch-1 and 9.6 µg ⋅ branch-1, the spiked recoveries of the three targets ranged from 97. 1% to 103. 1%, and the determination result of 7 mint cigarette filter samples by this method showed that the relative standard deviations ( RSD) were less than 3.0%. The content of menthol in the menthol cigarette filter was significantly higher than that of the traditional menthol cigarette filter, while the change of nicotine and triacetin content had no obvious change. [ABSTRACT FROM AUTHOR]

Ordered mesoporous carbon/graphene hybrids (OMCGs) with large specific surface areas (1795 m2 g−1) have been firstly synthesized by the direct self-assembly of soluble phenolic resin, an F127 triblock copolymer and tetraethyl orthosilicate (TEOS) on the surface of graphene oxide. The resulting OMCG electrode shows an advanced specific capacity of 330 F g−1, a high energy density of 38.1–32.3 W h kg−1 and a power density of 6.1–61.1 kW kg−1, and long cycle life. [ABSTRACT FROM AUTHOR]

Under physiological conditions, K(TPE)EFYp is converted to K(TPE)EFY containing hydroxyl by dephosphorylation of ALP and fluorescence is turned on. [Display omitted] • An enzyme-responsive biosensor with AIE properties. • A peptide-based Fluorescent supramolecular hydrogel (FSH) material. • Sol-gel phases transformation to determine alkaline phosphatase (ALP) activity. • "Turn-on" strategy due to the AIE effect has a higher sensitivity and a lower LOD. Alkaline phosphatase is an important biomarker for medical diagnosis. An enzymatic fluorescence supramolecular hydrogel with AIE properties was developed and used for sensing alkaline phosphatase in vitro and in living cells. In the presence of ALP, K(TPE)EFYp was partially converted to the hydrogelator K(TPE)EFY and self-assembled into nanofibers to form Hydrogel. With the sol–gel transition and the AIE effect, the fluorescence emission was turned on. The linear concentration range of ALP activity in vitro quantified by this method was determined as 0–3 U/L with a LOD at 0.02 U/L. In addition, cell imaging and serum experiment showed that K(TPE)EFYp could also be used to detect ALP activity in living cells and biological samples. [ABSTRACT FROM AUTHOR]

In the present study, a sensitive, efficient and repeatable method for the simultaneous extraction and determination of 13 types of phthalic acid esters (PAEs) in flavoring essence samples using magnetic graphene solid-phase extraction coupled with gas chromatography tandem mass spectrometry was developed. Due to the unique structure of magnetic graphene, it has several advantages, such as large surface area and fast separation ability. This unique structure not only provided strong magnetic responsiveness for the separation but also prevented the self-aggregation of graphene. The large delocalized p-electron system of graphene can form strong π-stacking interactions with the benzene ring. Thus, graphene may be also a good candidate adsorbent for the adsorption of benzenoid-form compounds. Several magnetic soild-phase extraction parameters, such as elution solvents, amounts of sorbents, enrichment time and desorption time were optimized. The optimized procedures for this method were performed by ultrasonication using ethyl acetate as elution solvent for 5 min. Under the optimal conditions, the developed method provided spiked recoveries of 75.0–105.3% with relative standard deviations of ~5.6% and limits of detection were 0.011–0.091 mg/kg. Good linear relationships were observed with the coefficient of determination (R2) > 0.993 for all the analytes. Finally, the validated method was successfully applied to the analysis of PAEs in real samples. [ABSTRACT FROM AUTHOR]

The essential oil was isolated using the water steam distillation from the peel of Citrus maxima (Burm.) Merr. cv. Shatian Yu with a yield of 0.31% (w/w). The essential oil sample were analyzed by GC-MS and total sixty six components were identified. The major compounds were found to be identical namely D-limonene (86.4%) and nootkatone (2.11%). The essential oil displayed broad spectrum antibacterial activity against a panel of pathogenic bacteria and was most effective against Bacillus licheniformis. Thus, pummelo essential oil could be a potential antimicrobial agent. [ABSTRACT FROM AUTHOR]