By gently bubbling nitrogen gas through beer, an effervescent beverage, both volatile and non-volatile compounds can be simultaneously sampled in the form of aerosol. This allows for fast (within seconds) fingerprinting by extractive electrospray ionization mass spectrometry (EESI-MS) in both negative and positive ion mode, without the need for any sample pre-treatment such as degassing and dilution. Trace analytes such as volatile esters (e.g., ethyl acetate and isoamyl acetate), free fatty acids (e.g., caproic acid, caprylic acid, and capric acid), semi/non-volatile organic/inorganic acids (e.g., lactic acid), and various amino acids, commonly present in beer at the low parts per million or at sub-ppm levels, were detected and identified based on tandem MS data. Furthermore, the appearance of solvent cluster ions in the mass spectra gives insight into the sampling and ionization mechanisms: aerosol droplets containing semi/non-volatile substances are thought to be generated via bubble bursting at the surface of the liquid; these neutral aerosol droplets then collide with the charged primary electrospray ionization droplets, followed by analyte extraction, desolvation, ionization, and MS detection. With principal component analysis, several beer samples were successfully differentiated. Therefore, the present study successfully extends the applicability of EESI-MS to the direct analysis of complex liquid samples with high gas content.

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A sensitive method based on a geometry-independent neutral desorption (GIND) in combination with extractive electrospray ionization mass spectrometry (EESI-MS) has been developed for fast detection of illicit additives such as sulfonamides and hormones in highly viscous cosmetic products. The method gave a low limit of detection (LOD) (in the range of 0.001-1 ng/g), acceptable relative standard deviation (RSD=6.8-11.4%) and reasonable recovery (87-116%) for direct measuring of nine types of hormones and sulfonamides in the cosmetic products. The average measurement time for two types of samples was less than 1 min. Trace amounts of analytes in commercial cosmetic products have been quantitatively detected, without any sample pretreatment. The experimental results showed that non-volatile illicit additives such as sulfonamides and hormones could be sensitively liberated using the GIND device for quantitative detection from the highly viscous cosmetic products, demonstrating that GIND-EESI-MS is a promising tool for high throughput, sensitive and quantitative analysis of highly complex viscous samples.

The olivine-type LiFePO 4 /C cathode materials were prepared via carbothermal reduction method using cheap Fe 2 O 3 as raw material and different contents of glucose as the reducing agent and carbon source. Their structural and morphological properties were investigated by X-ray diffraction, scanning electron microscope, transmission electron microscope, and particle size distribution analysis. The results demonstrated that when the content of the carbon precursor of glucose was 16 wt.%, the synthesized powder had good crystalline and exhibited homogeneous and narrow particle size distribution. Even and thin coating carbon film was formed on the surface of LiFePO 4 particles during the pyrolysis of glucose, resulting in the enhancement of the electronic conductivity. Electrochemical tests showed that the discharge capacity first increased and then decreased with the increase of glucose content. The optimal sample synthesized using 16 wt.% glucose as carbon source exhibited the highest discharge capacity of 142 mAh g −1 at 0.1C rate with the capacity retention rate of 90.4% and 118 mAh g −1 at 0.5C rate.

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