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Liquid–liquid separation, commonly referred to as oiling-out, frequently can occurs during crystallization, especially the anti-solvent crystallization process of phosphoryl compounds, and poses potential hurdle for high-quality product. Efficiently regulating oiling-out during crystallization remains a significant challenge. Among various techniques, ultrasound emerges as a green and effective approach to enhance the crystallization process. However, there is a dearth of in-depth research exploring the microscopic mechanisms of this process. Therefore, our research focused on the fructose-1,6-diphosphate (FDP), a typical phosphoryl compound, to gain a deeper understanding of how ultrasound influences the oiling-out process. The focused beam reflectance measurement (FBRM) technology was used to investigate the oiling-out phenomenon of FDPNa3 across various solvent ratios. In addition, the influence of ultrasound on the induction time was studied and the nucleation energy barrier was calculated. Finally, to further unravel the microscopic mechanisms, we utilized molecular simulation techniques to analyze the impact of ultrasound power on the dissolution-precipitation process. Our observations revealed a consistent oiling-out process that attainted a stable state regardless of the solvent employed. Notably, the results of the oiling-out induction time experiments indicated that ultrasound significantly reduced helped lower the nucleation energy barrier of FDP3- ions, thereby dismantling FDP3-clusters in solution. Thus, in turn, shortened the reduced induction time and promoted crystallization. Furthermore, ultrasound reduced the interactions between FDP3-ions and water molecules as well as FDP3- ions themselves. As simulated field intensity increased, these interaction forces gradually diminished, the thickness of the hydration layer surrounding the FDP3- clusters facilitating the disruption of clusters, ultimately enhancing the crystallization process.

This study investigates the removal efficiency of Cu2+ from wastewater using a composite hydrogel made of carbon nanotubes (CNTs), sodium alginate (SA), and polyacrylic acid (PAA) prepared by free radical polymerization. The CNTs@SA/PAA hydrogel’s structure and properties were characterized using SEM, TEM, FTIR, XRD, rheology, DSC, EDS, elemental mapping analysis, and swelling. The adsorption performance for Cu2+ was tested in batch adsorption experiments, considering the pH, dosage, initial concentration, and contact time. The optimal conditions for Cu2+ removal were pH 5.0, an adsorbent dosage of 500 mg/L, and a contact time of 360 min. The adsorption followed pseudo-second order kinetics. Isotherm analyses (Langmuir, Freundlich, Temkin, Dubinin–Radushkevich, Sips, Toth, and Khan) revealed that the Freundlich isotherm best described the adsorption, with a maximum capacity of 358.52 mg/g. A thermodynamic analysis indicated that physical adsorption was the main interaction, with the spontaneity of the process also demonstrated. This study highlights the high efficiency and environmental friendliness of CNT@SA/PAA composites for Cu2+ removal from wastewater, offering a promising approach for water treatment.

Objective: Heracles ultra-fast gas phase electronic nose was applied to establish a quick and effective differentiation method for American ginseng originated from varied places on the basis of different smell. Methods: Heracles ultra-fast gas phase electronic nose was used to analyze the smell of American ginseng originated from varied places and acquired chromatographic information of smell of sample American ginseng. The chromatographic peaks with strong separation intensity and discrimination ability were screened. Based on Kovats retention index and Arochembase database, the main odorant compounds of American ginseng from different producing areas were characterized. According to the relative odor activity value (ROAV), the contribution degree of the main difference compounds to the odor of American ginseng was analyzed by the odor threshold and relative content of the main difference compounds. PCA and DFA stoichiometry models were used for analysis. Results: Thirteen major differential compounds including propanaldehyde, n-valyl aldehyde and n-hexanal were screened out from ginseng of different origin by Heracles ultra-fast gas-phase electronic nose. Through the ROAV analysis of the main difference compounds, it was determined that n-hexal, propionic aldehyde, dodecal, n-valyl aldehyde, 2,3,5-trimethylpyrazine, methyl butyrate, 2-heptanol were the odor substances that contributed more to the odor of American ginseng. Among them, n-hexal was the key odor compounds that contributed the most to the odor of American ginseng. The contents of n-hexal, n-valental, 2,3,5-trimethylpyrazine and 2-heptanol were the highest in American ginseng from American . The contents of propionic aldehyde and methyl butyrate were the highest in American ginseng from Canadian. The content of dodecal was the highest in American ginseng from Jilin . PCA and DFA stoichiometric models were established. The recognition index of PCA model was 88. The cumulative discrimination index of DFA model was 100%. It was indicated that both PCA and DFA models could distinguish the odors of American ginseng from different producing areas, which could identify and analyze the odors of American ginseng samples. Conclusion: Heracles ultra-fast gas-phase electronic nose can quickly and effectively distinguish ginseng from different origin. This provides a new scientific basis for tracing the origin of ginseng.

IntroductionNatural melanin from Auricularia heimuer have numerous beneficial biological properties, which were used as a safe and healthy colorant in several industries.MethodsIn this study, single-factor experiments, Box-Behnken design (BBD), and response surface methodology (RSM) were employed to investigate the effects of alkali-soluble pH, acid precipitation pH, and microwave time on the extraction yield of Auricularia heimuer melanin (AHM) from fermentation. Ultraviolet-visible spectrum (UV-Vis), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscope (SEM), and high-performance liquid chromatography (HPLC) were used to analyze the extracted AHM. The solubility, stability, and antioxidant activities of AHM were also measured.ResultsThe results showed that alkali-soluble pH, acid precipitation pH, and microwave time significantly affected the AHM yield, with the following optimized microwave-assisted extraction conditions: alkali-soluble pH of 12.3, acid precipitation pH of 3.1, and microwave time of 53 min, resulting in an AHM extraction yield of 0.4042%. AHM exhibited a strong absorption at 210 nm, similar to melanin from other sources. FT-IR spectroscopy also revealed that AHM exhibited the three characteristic absorption peaks of natural melanin. The HPLC chromatogram profile of AHM showed a single symmetrical elution peak with a 2.435 min retention time. AHM was highly soluble in alkali solution, insoluble in distilled water and organic solvents, and demonstrated strong DPPH, OH, and ABTS free radical scavenging activities.DiscussionThis study provides technical support to optimize AHM extraction for use in the medical and food industries.