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21.
The confinement of CsPbX3 (X = Cl, Br, and I) perovskite nanocrystals (NCs) in a stabilized inorganic glass matrix is a new strategy for improving their long-term stability and promoting their applications in the optoelectronic field. Here, in situ nanocrystallization strategy is developed to precipitate CsPbBr3?xIx NCs with arbitrary I/Br ratio among an elaborately designed GeS2–Sb2S3-based chalcogenide glass matrix. Spherical CsPbBr3?xIx NCs are homogeneously distributed in the glass matrix after thermal treatment. The photoluminescence (PL) spectra show that the emission peaks of CsPbBr3?xIx NCs can be tuned from 570 nm to 722 nm with the replacement of Br by I. The fs transient absorption (TA) spectra reveal that there exists some structural defects in the NCs, leading to short PL decay life. This work would shed light on confining CsPbX3 NCs into glassy matrices, facilitating their future applications in photoelectronic fields.  相似文献   
22.
Many astonishing biological collective behaviors exist in nature, and artificial microrobotic swarms have been developed by emulating these scenarios. However, these microswarms typically have single structures and lack the adaptability that many biological swarms exhibit to thrive in complex environments. Inspired by viscoelastic fire ant aggregations and using a combination of experiment and simulation, a strategy to trigger ferrofluid droplets into forming microswarms exhibiting both liquid-like and solid-like behaviors is reported. By spatiotemporally programming an applied magnetic field, microswarms can be liquefied to implement reversible elongation with a high aspect ratio and solidified into entireties to perform overturning and bending behaviors. It is demonstrated that reconfigurability enables the microswarm to be a mobile dexterous micromanipulator, acting not only as a soft “octopus arm” to explore a confined environment and grasp a targeted object but also adaptively navigate multiple terrains, such as uneven surfaces, curved grooves, complex mazes, high steps, narrow channels, and even wide gaps. This microrobotic swarm can reconfigure both shapes and tasks based on the demands of the environment, presenting novel solutions for a variety of applications.  相似文献   
23.
Data Mining and Knowledge Discovery - Most research in machine learning for data streams has focused on classification algorithms, whereas regression methods have received a lot less attention....  相似文献   
24.
Sun  H.  Zhao  Z. B.  Yang  J. X.  Wang  Q. J. 《Journal of Materials Science》2022,57(6):4153-4165
Journal of Materials Science - The crystallographic orientation of TiB is one of the main factors that influence the microstructure and texture evolution of Ti-TiB composites. Different...  相似文献   
25.
Hao  Shijie  Wang  Zhonghao  Sun  Fuming 《Neural Processing Letters》2022,54(4):2759-2782
Neural Processing Letters - Scale variation is one of the primary challenges in object detection. Recently, different strategies have been introduced to address this challenge, achieving promising...  相似文献   
26.
Soybean hulls, the main byproduct in soybean processing, have many biological activities. However, the value of this byproduct is still far from being fully exploited. In this study, we investigated the anti-tyrosinase and antioxidant capacities in soybean hulls fermented by Lactobacillus plantarum ZLC-18 (L. plantarum ZLC-18). We found that L. plantarum ZLC-18 fermentation could markedly improve the anti-tyrosinase and antioxidant activities of soybean hulls. The anti-tyrosinase and antioxidant activities were positively correlated with the total phenolic and flavonoid contents. UPLCMS analysis suggested that phenolic compounds (daidzin, genistin, vanillic acid and so on) were increased in soybean hulls after fermentation, and some of these compounds were shown to have anti-tyrosinase and antioxidant activities. Our study demonstrates that fermentation is an efficient strategy to enhance the bioactive function of soybean hulls. Moreover, this study provides evidence that soybean hulls can be used as a kind of functional food ingredient, thereby improving their economic benefits.  相似文献   
27.
Chemistry and Technology of Fuels and Oils - For shale gas wells, plunger lift is challenged by the difficulties like difficult tool tripping in and high operation risks due to the liquid phase...  相似文献   
28.
In this study, the effect of high-intensity ultrasound (HIUS) (200 and 400 W for 0, 5, 10 and 15 min respectively) on conformational changes, physicochemical, rheological and emulsifying properties of scallop (Patinopecten yessoensis) myofibrillar protein (SMP) was investigated. HIUS-treated SMP had lower α-helix content and higher β-sheet content compared with the native SMP. HIUS treatment induced the unfolding of SMP and increased the surface hydrophobicity. The particle size of SMP decreased and the absolute zeta-potential increased after ultrasonication, which in turn increased the solubility of SMP. The conformational changes and the improvement of physicochemical properties of SMP increased the ability for SMP to lower the interfacial tension at the oil–water interface and increased the percentage of adsorbed protein. As a result, the emulsifying properties, rheological properties of SMP and storage stability of emulsions were also improved. In conclusion, HIUS treatment has future potential for improving the emulsifying properties of SMP.  相似文献   
29.
The structural diversity of polyphenols and the inherent limitations of current extraction techniques pose a challenge to extract polyphenols using a simple and green method. Hence, in this study, a method was developed to simultaneously fractionate multiple classes of polyphenols by only varying ethanol-water solutions. Honeybush tea, which is rich in polyphenols, was selected as a model for this study. Solvent extraction followed by solid-phase extraction (SPE) was developed to obtain a polyphenol-rich fraction from six honeybush samples. Based on a gradient elution programme (10%, 30%, 50%, 70% and 90% (v/v) ethanol-water solution) of SPE, the Strata X cartridge showed a better recovery of most targeted polyphenols under 0.9 mL of the drying volume and 1 mL min−1 of the dispensing speed. The elution programme for fractionating most polyphenols was as follows: single elution with 50% ethanol, followed by twice elution with 70% ethanol. The antioxidant capacity was used to analyse the differences among the polyphenol-rich fractions from six honeybush samples. Principal component analysis (PCA) revealed that unfermented C. genistoides (GG) has the greatest antioxidant capacity among the honeybush species studied. Additionally, mangiferin, isomangiferin and vicenin-2 were the main contributors to the antioxidant capacity in six honeybush fractions according to the correlation study.  相似文献   
30.
Zhao  Ruiyu  Wang  Yi Mou  Li  Jie  Meng  Wenhua  Yang  Chunli  Sun  Chongxiang  Lan  Xuefang 《Journal of Applied Electrochemistry》2022,52(3):573-581
Journal of Applied Electrochemistry - Ni, Ce, and Ta modified Ti/SnO2–Sb2O5–RuO2 anodes were first prepared by thermal decomposition strategy and applied for Orange G degradation to...  相似文献   
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