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As a kind of fuel with low‐carbon emissions, hydrogen‐rich syngas has a large resource potential and is a promising alternative energy resource. A series of experiments in a constant volume combustion bomb are carried out to investigate the effects of turbulence and diffusional–thermal (DT) instability on a hydrogen‐rich syngas turbulent premixed flame. The flow field in the constant volume combustion bomb is calibrated, and the turbulent flow field's homogeneity and isotropy were investigated. The effects of different speeds of fan (1366–4273 rpm), hydrogen fractions (55%–95%), pressures (1.0–3.0 bar), and equivalence ratios (0.6–1.0) on the hydrogen‐rich syngas turbulent premixed flame are studied. According to the analyses, the flow field in the experimental device exhibits good homogeneous and isotropic characteristics. With the increase of turbulence intensity, equivalence ratio, hydrogen fraction, or pressure, the turbulent flame propagation speed increases gradually. As the hydrogen fraction increases or the equivalence ratio decreases, the effective Lewis number decreases, and the effect of DT instability on the flame increases. The research in this article is crucial for the clean and efficient utilization of hydrogen‐rich syngas and the design of related burners. [ABSTRACT FROM AUTHOR]

To investigate the optimal extraction process and antioxidant activity of anthocyanins of Lycium ruthenicum Murr., the anthocyanins of Lycium ruthenicum Murr. were extracted by ultrasonic enzyme-assisted extraction, ethanol/ammonium sulfate aqueous two-phase extraction, ethanol/sodium dihydrogen phosphate aqueous two-phase extraction, and the extraction process was optimized by response surface methodology, the antioxidant model of BRL 3A cells induced by t-BHP was used to explore the protective effect of Lycium ruthenicum Murr. anthocyanins on oxidative stress. The results showed that the yield of ultrasonic enzyme assisted extraction was (17.92 ± 0.04) mg/g; the yield of ethanol/ammonium sulfate aqueous two-phase extraction was (15.46 ± 0.31) mg/g; the extraction yield of ethanol/ sodium dihydrogen phosphate aqueous two-phase system was (15.02 ± 0.19) mg/g. The in vitro antioxidant experiments showed that the antioxidant activity of anthocyanins (LRN) extracted by EtOH/ (NH4)2SO4aqueous two-phase extraction was the strongest, purified EtOH/(NH4)2SO4 aqueous two-phase extraction of anthocyanins (LRNA) can alleviate t-BHP-induced oxidative damage by reducing ROS production in cells. In summary, this process is convenient and stable and can be used for the extraction of anthocyanins from Lycium ruthenicum Murr. At the same time, it also proves that LRN has the strongest antioxidant activity. [ABSTRACT FROM AUTHOR]

The combustion characteristics of ammonia/hydrogen/air mixtures flame under different equivalent ratios (0.6–1.0), and hydrogen ratio (0.3–0.5) in a wide range of turbulence intensity were investigated. The result shows both differential diffusion and flame chemistry affect the flame morphology and burning velocity of lean and stoichiometric mixtures. With the increase of hydrogen ratio, not only can chemical reaction be enhanced, but also heat and mass diffusion of the flame front can be promoted, thus accelerating flame propagation. In addition, the strong turbulent stretch of the turbulent field gradually plays a dominant role in the development of flame and causes the flame to wrinkle even more. Based on the turbulent flame Reynolds number (Re T,flame), the accelerated propagation processes are analyzed, and further, the influences of differential diffusion and turbulent stretching are taken into account by Le and Ka numbers. The general correlation of turbulent burning velocity (S T) is obtained, and the applicability of the correlation based on Da and Ka for ammonia/hydrogen/air mixtures turbulent combustion is verified. In addition, a unified scaling of turbulent burning velocity (S T) suitable for different equivalent ratios and hydrogen content conditions is obtained by rearranging with Le. • Effect of differential diffusion and turbulent stretch on S T are studied. • The self-accelerating propagation is verified and propose the correlation of S T. • A unified scaling of S T is obtained based on Da , Ka , and Le. [ABSTRACT FROM AUTHOR]