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Through pharmacological activity research, an increasing number of natural products and their derivatives are being recognized for their therapeutic value. In recent years, studies have been conducted on Corydalis yanhusuo W.T. Wang, a valuable medicinal herb listed in the Chinese Pharmacopoeia. Protopine, one of its components, has also become a research hotspot. To illustrate the identification, metabolism, and broad pharmacological activity of protopine and the botanical preparations containing it for further scientific studies and clinical applications, an in-depth and detailed review of protopine is required. We collected data on the identification and quantification, metabolism and pharmacokinetics, pharmacological activities, and botanical preparations of protopine from 1986 to 2021 from the PubMed database using “protopine” as a keyword. It has been shown that protopine as an active ingredient of many botanical preparations can be rapidly screened and quantified by a large number of methods (such as the LC-ESI-MS/MS and the TLC/GC-MS), and the possible metabolic pathways of protopine in vivo have been proposed. In addition, protopine possesses a wide range of pharmacological activities such as anti-inflammatory, anti-platelet aggregation, anti-cancer, analgesic, vasodilatory, anticholinesterase, anti-addictive, anticonvulsant, antipathogenic, antioxidant, hepatoprotective, neuroprotective, and cytotoxic and anti-proliferative activities. In this paper, the identification and quantification, metabolism and pharmacokinetics, pharmacological activities, and botanical preparations of protopine are reviewed in detail to lay a foundation for further scientific research and clinical applications of protopine.

For the design and safety studies of steam generator in the China LEAd-based Reactor (CLEAR) project, it is necessary to investigate the consequences of a Steam Generator Tube Rupture (SGTR) accident which could result in a reaction between Lead-Bismuth Eutectic (LBE) and highly pressurised water. Some experiments have been conducted to investigate the thermal-hydraulic behaviour of the molten LBE/water interface; the whole fragmentation processes of these experiments were visually observed with a high-speed video camera, and the transient pressure histories were measured by high-frequency piezoelectric pressure sensors. The effects of LBE temperature, water temperature, nozzle diameter and injection velocity were investigated. Visualisation films indicated that the explosion phenomenon happened readily at lower water temperature. The peak pressure decreased with increasing water temperature, nozzle diameter and injection velocity. However, the peak pressure first increased and then decreased as the LBE temperature increased. The shape of the debris became round at higher water temperature, and a needle-like shape was observed at lower temperatures. Debris analysis results showed that the debris sizes of 2.8–6.7 mm had the largest mass fraction. By comparison with the theoretical calculation, it was found that the fragment diameters measured in the present study agreed well with Weber number theory. Thus, it was demonstrated that the fragmentation mechanism was controlled by shearing stress under the present experimental conditions.