Introduction: Dandelion (Taraxacum mongolicum Hand.-Mazz.) is a perennial herb with diverse pharmacological effects. The development and utilization of dandelion have attracted much attention.Objectives: Our aims were to provide a reference basis for the identification of the origin of dandelions and to study the influence of their origin on their quality. MethodsHigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was used to analyze metabolites from dandelions from four different geographical regions in China, namely Gansu, Henan, Shanxi, and Jiangsu.Metabolite analysis was performed using orthogonal partial least-squares discriminant analysis, and to identify potential metabolic pathways, MBRole was used to perform Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis.Results: Principal component analysis revealed that the chemical components of dandelions sampled from the four regions showed noticeable differences.Twenty-six, six, six, eight, eight, and fifteen differentially produced metabolites were identified upon comparison between Gansu and Jiangsu, Gansu and Shanxi, Gansu and Henan, Henan and Shanxi, Henan and Jiangsu, and Shanxi and Jiangsu, respectively. These differentially produced metabolites were mainly phenolic compounds. Further, KEGG pathway enrichment analysis showed that the main metabolic pathways involved were biosynthesis of phenylpropanoids and flavonoids. Conclusion:The methods reported herein can be used to identify the origin of dandelions; moreover, our results can serve as a reference basis for future studies.

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It is of practical significance to study the multi-physical processes of solid state nuclear systems for device design, safety analysis, and operation guidance. This system generally includes three multi-physical processes: neutronics, heat transfer, and thermoelasticity. In order to analyze the multi-physical field behavior of solid state nuclear system, it is necessary to analyze the laws of neutron flux, temperature, stress, and other physical fields in the system. Aiming at this scientific goal, this paper has carried out three aspects of work: (1) Based on Galerkin’s finite element theory, the governing equations of neutronics, heat transfer, and thermoelasticity have been established; (2) a neutronics-thermal-mechanical multi-physical finite element analysis code was developed and verified based on benchmark examples and third-party software for multi-physical processes; (3) for a solid state nuclear system with a typical heat pipe cooled reactor configuration, based on the analysis code developed in this work, the neutronics-thermal-mechanical coupling analysis was carried out, and the physical field laws such as neutron flux, temperature, stress, etc., of the device under the steady-state operating conditions were obtained; and (4) finally, the calculation results are discussed and analyzed, and the focus and direction of the next work are clarified.

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