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571.
572.
Julie P. Vanegas Amanda Reusch Mark J. Fink Brian S. Mitchell 《Particle & Particle Systems Characterization》2023,40(11):2300052
Alkanes such as n-hexane have been used as co-solvents in the production of functionalized semiconductor nanoparticles from alkenes and alkynes using Reactive High Energy Ball Milling (RHEBM) under the assumption that they are non-reactive under typical milling conditions. In this paper, a comparative study with two hydrocarbon solvents of comparable chain length, 1-hexyne, and n-hexane, and their milling products using three different commercially available silicon precursors, namely single crystal silicon wafers and polycrystalline particles having a nominal size of 4 µm and 1 mm, is reported. It is found that nanoparticle formation and surface functionalization in all the three silicon systems occurs only with 1-hexyne; n-hexane is non-reactive and does not lead to appreciable functionalized nanoparticle formation under the conditions studied. Nanoparticles (where formed) and microparticle byproducts of appropriate samples are characterized by Transmission electronic microscope (TEM), Fourier transform infrared (FTIR), Photoluminiscence spectroscopy (PL), Nuclear magnetic resonance 1H/13C NMR, and thermogravimetry TGA to separately confirm nanoparticle formation and surface functionalization. 相似文献
573.
Cactus is a tropical fruit with a high nutritional value; however, little information is available regarding the comprehensive utilization of its byproducts. This study aimed to explore the composition and nutritional value of cactus fruit seed oil (CFO) and reveal the effects of ultrasound-assisted extraction and traditional solvent extraction on oil quality. Foodomics analysis showed that CFO extracted using a traditional solvent is rich in linolenic acid (9c12cC18:2, 57.46 ± 0.84 %), α-tocopherol (20.01 ± 1.86 mg/100 g oil), and canolol (200.10 ± 1.21 μg/g). Compared to traditional solvent extraction, ultrasound-assisted extraction can significantly increase the content of lipid concomitants in CFO, whereas excessive ultrasound intensity may lead to the oxidation of oils and the formation of free radicals. Analysis of the thermal properties showed that ultrasound had no effect on the crystallization or melting behavior of CFO. To further demonstrate the nutritional value of CFO, a lipopolysaccharide (LPS)-induced lipid metabolism imbalance model was used. Lipidomics analysis showed that CFO significantly reduced the content of oxidized phospholipids stimulated by LPS and increased the content of highly bioactive metabolites such as ceramides, thus alleviating LPS-induced damage in C. elegans. Hence, CFO is a functional oil with high value, and ultrasound-assisted extraction is advocated. These findings provide new insights into the comprehensive utilization of cactus fruits. 相似文献
574.
Wei Liu Jiage Yu Marshet Getaye Sendeku Tianshui Li Wenqin Gao Guotao Yang Yun Kuang Xiaoming Sun 《Angewandte Chemie (International ed. in English)》2023,62(40):e202309882
The direct seawater electrolysis at high current density and low overpotential affords an effective strategy toward clean and renewable hydrogen fuel production. However, the severe corrosion of anode as a result of the saturation of Cl− upon continuous seawater feeding seriously hamper the electrolytic process. Herein, cobalt ferricyanide / cobalt phosphide (CoFePBA/Co2P) anodes with Cap/Pin structure are synthesized, which stably catalyze alkaline saturated saline water oxidation at 200–2000 mA cm−2 over hundreds of hours without corrosion. Together with the experimental findings, the molecular dynamics simulations reveal that PO43− and Fe(CN)63− generated by the electrode play synergistic role in repelling Cl− via electrostatic repulsion and dense coverage, which reduced Cl− adsorption by nearly 5-fold. The novel anionic synergy endow superior corrosion protection for the electrode, and is expected to promote the practical application of saline water electrolysis. 相似文献
575.
Yuhong Zhang Weisheng Huang Xiaosong Yang 《Journal of Nonlinear Modeling and Analysis》2023,5(2):228-246
In this paper, we investigate the boundary of the attraction basin of a class of piecewise linear systems arising from anti-stable linear systems with saturated linear state feedback. In three-dimensional cases, for this class of systems, we prove that the equilibrium points other than the origin lie on the boundary of the attraction basin of the origin. This gives strong evidence that the boundary of the attraction basin is homeomorphic to a sphere. Some examples are provided to illustrate the results. 相似文献
576.
对人教版、鲁科版、苏教版等3种版本教材中有关电解饱和食盐水的内容进行比较分析,系统地从宏观和微观角度阐明电解饱和食盐水的化学本质。研究结果有助于深化对电解饱和食盐水及氯碱工业的科学性认识,进一步为多种教材的综合利用和教师教学设计提供必要的理论依据。 相似文献