Laser-induced breakdown spectroscopy (LIBS) is a sensitive optical technique capable of rapid multielemental analysis. The development of this technique for elemental analysis in traditional Chinese medicine can eventually revolutionize the pharmaceutical industry. The detection and identification of real and fake elements in traditional Chinese medicine is very important, and saffron is a typical representative. In this study, the in situ detection of the elements and exogenous heavy metals in saffron is performed by LIBS. To test the identification ability of the model combined with LIBS and principal component analysis, three samples (saffron, radish, and corn silk) were used as target materials. Observable characteristic lines in spectra of saffron include Ca, Fe, Mg, Al, Mn, Sr, Ba, Ti, Na, K, P, and Si. The observed spectral lines of H, O, and N are mainly affected by the air composition, while the CN molecular bands also exist. In the air pollutant sedimentation simulation, the intensity of Cu and Pb as exogenous elements in the spectrum is proportional to the concentration of the solution used for contamination. Saffron and adulterants can be separated in the scoring chart. Besides, with the increase in the cardinal number of variables, the resolution effect is more and more obvious. In general, LIBS has good discrimination ability while performing a rapid synchronous analysis of elements. The result has proved that LIBS is a powerful tool in the research of traditional Chinese medicine.

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Chlorobenzene is one of the Persistent Organic Pollutants (POPs) threatening human health. It is significant to study the degradation mechanism under external electric fields. Based on the density functional theory, the physical and dissociation properties including C–Cl bond length, total energy, dipole moment, frontier orbital energy, energy gap, IR spectrum, UV-vis absorption spectrum and potential energy curve are studied under external electric fields. According to these results, it is found that the C–Cl bond length becomes longer and tends to break with the increase of external electric field and the energy gap decreases with the increase of positive as well as negative external electric field. Moreover, the dissociation barrier in potential energy curve decreases and equilibrium bond length increases with increase of positive external electric field. And when external electric field reaches 0.040 atomic units ([Formula: see text], 1 atomic [Formula: see text], the dissociation barrier disappears which means that degradation of chlorobenzene occurs under strong external electric field due to the breakage of C–Cl bond. These results provide important references for studying the degradation mechanism of chlorobenzene under strong external electric fields.

One misprint in our manuscript is reported and corrected.

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