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[Display omitted] • A comprehensive approach for characterization of saffron samples was developed. • In-depth identification of crocins was achieved via a targeted UPLC-ESI/MS n method. • Non-crocin components were identified based on a non-targeted UPLC-ESI/MS2 method. • 32 new crocins were identified and 6 structures were reported for the first time. • 91 non-crocin components were discovered, including 43 new compounds. As a valuable medicinal and edible plant, C rocus sativus L. has had wide applications since ancient times. Herein, a comprehensive approach for characterization of constituents in saffron was established based on the combination of targeted and non-targeted strategies. A targeted UPLC-ESI/MS n strategy was applied for in-depth identification of crocins, and a non-targeted UPLC-ESI/MS2 approach characterized other components. This integration strategy was used to analyze ingredients in 21 batches of saffrons from 6 origins. Forty-seven crocins belonging to 8 types were identified including 32 new crocins. Among them, 6 new compounds with specific structures were reported for the first time, i.e. trans -6(G, 2G), trans -4(GT, g), trans -3(GT), cis -3(GT), methyl ester- trans -2(G) and methyl ester- cis -2(G). Besides, 91 non-crocin components were identified including 43 new compounds. Based on systematic investigation of crocins and non-crocins, we found that crocins were the critical components to distinguish saffrons from different origins, especially between domestic and foreign samples. [ABSTRACT FROM AUTHOR]

Qingfei Paidu Decoction is a Chinese medicine formula that has been proved effective in the treatment of coronavirus disease 2019. However, the comprehensive separation and characterization of Qingfei Paidu Decoction are of a great challenge due to the diversity of chemical components in a wide range of polarity. In this study, a triplex off‐line two‐dimensional liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry is developed for the analysis of Qingfei Paidu Decoction. One reversed‐phase liquid chromatography×hydrophilic interaction liquid chromatography system and two reversed‐phase liquid chromatography×reversed phase liquid chromatography systems were constructed to separate polar components and weak‐polar components in Qingfei Paidu Decoction, respectively. Benefiting from the good orthogonality of two‐dimensional liquid chromatography and high sensitivity of quadrupole time‐of‐flight MS, chemical components with different polarities and content were discovered. A total of 749 peaks were detected in positive and negative ionization mode and presented as a four‐dimensional data plot. Meanwhile, 498 compounds belonging to 14 categories were tentatively identified. These results provide good supplementary to elucidate the material basis of Qingfei Paidu Decoction. The triplex off‐line two‐dimensional liquid chromatography‐quadrupole time‐of‐flight mass spectrometry strategy can be a powerful and efficient tool for the separation and characterization of chemical substances in traditional Chinese medicine formulas. [ABSTRACT FROM AUTHOR]

This paper presents the experimental and numerical investigations on steel–concrete–PVC SHS joints under axial compression, in which PVC pipes were used as the inner tube of chord member and SHS steel tubes were used as the outer tube of chord member. A total of 22 joints with different brace to chord width ratio ( β ), hollow ratio of chord ( φ ) and shapes of PVC inner tube of chord were tested, in which two traditional hollow joints and two grouted joints were tested for comparison. The effects of brace to chord width ratio ( β ), hollow ratio of chord ( φ ), grout strength and shapes of PVC inner tube of chord on the structural behavior of steel–concrete–PVC SHS joints under axial compression were evaluated. Failure load and initial stiffness of traditional joints are remarkably enhanced by grouting the chord member along its full length, but the ductility is greatly deteriorated. On the other hand, the failure load and initial stiffness of steel–concrete–PVC SHS joints are improved with the increase of the β ratio. Whereas, the failure loads of steel–concrete–PVC SHS joints are weakened with the increase of the φ ratio. Furthermore, the grout strength has insignificant influence on the failure loads of steel–concrete–PVC SHS joints under axial compression. In addition, the steel–concrete–PVC SHS joints with large φ ratio show good ductility. Chord web deflection is larger than the chord flange indentation for steel–concrete–PVC SHS joints. For steel–concrete–PVC SHS joints with small φ ratio, the root of brace yielded first, while in the ultimate limit state, chord member around the joint intersection region were in the elastic phase. For steel–concrete–PVC SHS joints with large φ ratio, chord member around the joint intersection region yielded first, while in the ultimate limit state, the root of brace were fundamentally in the elastic phase. The design equations are proposed based on parametric FE analysis results for steel–concrete–PVC SHS joints under axial compression, which are verified to be more accurate. [ABSTRACT FROM AUTHOR]