We proposed a method for the extraction of medicinal herbs, called ultrasound‐assisted centrifugal extraction, and an online solvent concentration method. These techniques were coupled with two countercurrent chromatography systems and applied to the continuous extraction and online isolation of chemical constituents from Inonotus obliquus. Raw plants were extracted using a two‐phase petroleum–ethanol–water (2.0:1.0:2.0, v/v/v) process, and then the aqueous and organic phases were concentrated using the proposed online solvent concentrator. The countercurrent chromatography preparation prior to separation includes pumping of the two‐phase solution, rotating column, and equilibrium column. Following online concentration, the extracted solution was pumped into a second countercurrent chromatography process for separation. During separation, the extraction solution and concentrated extract were prepared automatically. Upon completion of the first cycle of ultrasound‐assisted centrifugal extraction/two countercurrent chromatography, the second cycle experiment starts. This process can be indefinitely repeated. In this study, six target compounds with purities above 97.71% were successfully extracted and isolated online using a two‐phase solvent system consisting of n‐hexane‐ethyl acetate‐acetonitrile (4.5:1.5:5.5, v/v/v) and n‐hexane–ethyl acetate–methanol–water (0.4:3.0:1.5:2.5, v/v/v/v). Compared to conventional extraction methods, the instrumental setup of the proposed method provides enhanced automation, efficiency, purity, and systematic extraction and isolation of natural products.

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The uncertainty of distributed energy (DG) and load in the electric–gas combined system (EGCS) requires EGCS to have higher dispatching capacity. A novel strategy is introduced in this paper to operate EGCS considering dispatchability evaluation indexes in order to improve the dispatchability of EGCS. Firstly, the paper describes the physical architecture of EGCS and its main devices. Based on the typical structure of EGCS, the main coupling modes between the two networks are analyzed and summarized, and a power flow model of deep coupling EGCS is established. Then, it proposes a unified quantitative modeling method of dispatchability, and qualitatively analyzes the dispatchability capability of different types of resources in the system through the definition, connotation, and multi-dimensional attributes of EGCS dispatchability. In order to characterize the strength of the overall dispatchability of EGCS, two evaluation indexes, upward/downward dispatchability margin, are proposed. The case study validates the applicability of the proposed dispatchability indexes through simulation. The uncertainties existing in various sources, namely networks and loads of EGCS, the output power of wind farms, and photovoltaic plants, are analyzed emphatically through actual data of a certain area. The EGCS economic dispatching model is established by considering the DG output prediction errors, introducing the expected penalty term of insufficient dispatchability into the objective function, and calculating the dispatchability margin through the simulation model to quantitatively analyze the dispatchability capability of the system.

In this study, an efficient method that employs 5‐lipoxygenase and acetylcholinesterase as biological target molecules in receptor–ligand affinity ultrafiltration–liquid chromatography was developed for the screening of enzyme inhibitors derived from the Astragalus membranaceus stems and leaves. The effects of the extraction time, number of extraction cycles, ethanol concentration, and liquid–solid ratio on the total yield of the target compounds were investigated using response surface methodology, and the bioactive components were isolated using a combination of semi‐preparative high‐performance liquid chromatography and high‐speed countercurrent chromatography via a two‐phase solvent system consisting of n‐hexane–ethyl acetate–methanol–water (1:6:2:6, v/v/v/v). Subsequently, 10 naturally‐occurring bioactive components in the Astragalus membranaceus stems and leaves, including wogonin, ononin, isoquercitrin, calycosin‐7‐glucoside, 3‐hydroxy‐9,10‐dimethoxyptercarpan, hyperoside, 7,2′‐dihydroxy‐3′,4′‐dimethoxyisoflavan, baicalein, calycosin, and soyasaponin, were screened using affinity ultrafiltration to determine their potential effects against Alzheimer's disease. Consequently, all target compounds had purities higher than 95.0%, and the potential anti‐Alzheimer's disease effect of the obtained bioactive compounds was verified using molecular docking analysis. Based on the results, the back‐to‐back screening of complex enzyme inhibitors and separation of the target bioactive compounds using complex chromatography could provide a new approach to the discovery and preparation of natural active ingredients.