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The amine-decorated microporous metal-organic framework CAU-1 was readily synthesized and activated using a home-made efficient protocol. It exhibited a high heat of adsorption for CO 2 , high CO 2 uptake capacity, and an impressive selectivity for CO 2 over N 2 . At 273 K and up to 1 atm, CO 2 uptake capacity can reach as much as 7.2 mmol g À1 . Comparatively, the CH 4 and N 2 uptakes at 273 K and 1 atm were only 1.34 mmol g À1 and 0.37 mmol g À1 , respectively. The CO 2 /N 2 selectivity was 101 : 1 at 273 K. The isosteric heat of adsorption (Q st ) for CO 2 was $48 kJ mol À1 at the onset of adsorption, and it decreases to $28 kJ mol À1 at higher CO 2 pressures. Furthermore, CAU-1 can adsorb 2.0 wt% and 4.0 wt% hydrogen at 77 K under 1 atm and 30 atm, respectively. The adsorption characteristics of CAU-1 for methanol investigated in situ with a quartz crystal microbalance (QCM), indicated that this particular MOF structure can be used as a highly sensitive sensor for methanol detection such as direct methanol fuel cells. Recently, the basic properties of amine functionalized MOF were tested in Knoevenagel condensation reactions, 14,15 and Couck et al. 16 found that at low surface coverage, the CO 2 /CH 4 selectivity of the amine functionalized MIL-53(Al) was larger than that of the parent MIL-53(Al).

Various MOFs with tailored nanoporosities have recently been developed as potential storage media for CO 2 and H 2 . The composites based on Cu-BTC and graphene layers were prepared with different percentages of graphene oxide (GO). Through the characterization analyses and gas adsorption experiments, we found that the nanosized and well-dispersed Cu-BTC induced by the incorporation of GO greatly improved the carbon dioxide capture and hydrogen storage performance of the composites. The materials obtained exhibited about a 30% increase in CO 2 and H 2 storage capacity (from 6.39 mmol g À1 of Cu-BTC to 8.26 mmol g À1 of CG-9 at 273 K and 1 atm for CO 2 ; from 2.81 wt% of Cu-BTC to 3.58 wt% of CG-9 at 77 K and 42 atm for H 2 ). Finally, the CO 2 /CH 4 and CO 2 /N 2 selectivities were calculated according to single-component gas sorption experiment data.

A toroidal dipole in metasurfaces provides an alternate approach for the excitation of high-Q resonances. In contrast to conventional multipoles, the toroidal dipole interaction strength depends on the time derivative of the surrounding electric field. A characteristic feature of toroidal dipoles is tightly confined loops of oscillating magnetic field that curl around the fictitious arrow of the toroidal dipole vector.

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Illegal drug smugglings and crimes have long been a global concern, and an apparatus which can identify drugs on-the-spot is urgently demanded by law enforcement. A thermal desorption acetone-assisted photoionization miniature ion trap mass spectrometer was developed for on-site and rapid identification of illegal drugs at checkpoints. Acetone was chosen for dopant-assisted photoionization, and the sensitivity of selected drugs was further enhanced with protonated analyte molecular ions [M + H]+. For example, the sensitivity of ephedrine was improved by as high as 22-fold. The mass discrimination effect, which was usually considered as a shortcoming of ion trap mass analyzer, was ingeniously utilized to eliminate the protonated acetone reagent ions and maximize the trapping efficiency of analyte ions in mass analyzer. Twenty-seven drugs were analyzed, and the limits of detection (LODs) of selected illegal drugs were at the nanogram level with analysis time of 2 s. Analyte/dopant ion peak intensity ratios in mass spectra could be used for quantitation to improve the quantitative analysis performance of miniature ion trap mass spectrometer equipped with a discontinuous atmospheric pressure interface (DAPI) with the prerequisite that dopant ions and analyte ions could be simultaneously and effectively trapped by the ion trap. The RSD of signal intensity was reduced from 25.3% to 8.5%, and the linear range was extended from 0.5–25 to 0.5–100 ng/μL for methamphetamine. A temperature-resolved thermal desorption sampling strategy was developed and used to distinguish illegal drug components in plant-based drug samples and drinks containing illegal drugs.