Water radical cations, the crucial intermediates in many aqueous reactions and biochemical processes, are difficult to be experimentally investigated due to its short lifetime and low abundance. Herein, a homemade device based on energy-tunable discharge was employed to deposit suitable amounts of energy to atmospheric pressure pure water vapor for abundant production of water radical cations, which were stabilized as (H 2 O) n +• (n=2-5) with the maximal abundance (≥ 8.3×10 6 cps) for (H 2 O) 2 +• as characterized by mass spectrometry (MS).The abundance of water radical cations was optimized by adjusting the experimental parameters such as discharge voltage (2.5 kV), temperature of the MS inlet (140 o C), carrier gas flow (20 mL/min) and the distance between the discharge tip and the MS inlet (12 mm). The ambient formation of water radical cations was further confirmed by the high reactivity of the as-prepared water radical cations, which instantly reacted with benzene, ethyl acetate and dimethyl disulfide, showing rich chemistry with the ionic and radical characters. Moreover, the computations confirm that the O-O single-electron bound dimer (B) as well as the hydronium hydroxyl radical complex (A) accounts for the unusual chemistry of the water radical cations, providing a facile approach to access the high reactivity of water radical cations under the ambient condition.

A novel strategy to trace the origins of commercial pharmaceutical products has been developed based on the direct chemical profiling of the pharmaceutical products by surface desorption atmospheric pressure chemical ionization mass spectrometry (DAPCI-MS). Besides the unambiguous identification of active drug components, various compounds present in the matrixes are simultaneously detected without sample pretreatment, providing valuable information for drug quality control and origin differentiation. Four sources of commercial amoxicillin products made by different manufacturers have been successfully differentiated. This strategy has been extended to secerning six sources of Liuwei Dihuang Teapills, which are herbal medicine preparations with extremely complex matrixes. The photolysis status of chemical drug products and the inferior natural herd medicine products prepared with different processes (e.g., extra heating) were also screened using the method reported here. The limit of detection achieved in the MS/MS experiments was estimated to be 1 ng/g for amoxicillin inside the capsule product. Our experimental data demonstrate that DAPCI-MS is a useful tool for rapid pharmaceutical analysis, showing promising perspectives for tracking the entire pharmaceutical supply chain to prevent counterfeit intrusions.

Two Keggin-type U(vi)-containing tungstophosphates with sandwich structure were synthesized and characterized. Compound 1 presents excellent catalytic activity towards the condensation cyclization of sulfonyl hydrazines with 1,3-diketones to synthesize sulfonyl pyrazoles.

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Determination of uranium isotopic ratio (235 U/ 238 U) using extractive electrospray ionization tandem mass spectrometry