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Hematoxylin has a V-shaped chiral geometry, but its potential in chiroptical self-assembled materials is underdeveloped. Herein, three novel V-shaped chiral hematoxylin derivatives were synthesized, and they showed extended skeletons as well as photophysical and chiroptical behaviors. Moreover, their host–guest interactions with C60 were investigated. Our findings could aid in the design and synthesis of novel chiral host molecules from natural products. [ABSTRACT FROM AUTHOR]

The flotation results show that Ca2+ significantly reduces the flotation recovery of scheelite using single dodecylamine (DDA) or single sodium oleate (NaOL), whereas Ca2+ hardly affects scheelite recovery using mixed collectors DDA/NaOL. Zeta potential measurements and solution chemistry confirm that the zeta potential of scheelite shows a significant positive shift after conditioning of Ca2+, which hinders the adsorption of same positively charged DDA on the mineral surface. Simultaneously, the addition of Ca2+ consumes single NaOL and generates Ca(OL)2. As for DDA/NaOL, the predominant components are RNH3+ and RCOO− at pH 7; they form new highly active complexes through electrostatic attraction, reducing adverse effect of Ca2+. Fourier transform infrared spectroscopy measurements and adsorption measurements further confirm that the pre-adsorption of Ca2+ does not interfere with the adsorption of mixed collectors. [ABSTRACT FROM AUTHOR]

The floatability of scheelite and calcite in the presence of single depressant (SHMP or H3Cit) and mixed depressant (SHMP/H3Cit) was studied by microflotation experiments and artificial mixed mineral experiments. Solution chemical calculation, zeta potential tests, thermodynamic analysis and XPS analysis were used to explain the relevant depressive mechanism. Mixed depressant (SHMP/H3Cit) exhibited excellent selective depressive effect on calcite. The optimal molar ratio of SHMP to H3Cit was 1:4. The depressant SHMP and H3Cit can be chemically bonded with Ca2+ to form CaHPO4 and Ca3(Cit)2 at pH 8. The CaHPO4 was more easily formed than Ca3(Cit)2 on the mineral surface, which indicated that the depressive effect of SHMP was stronger than H3Cit. The SHMP and H3Cit of the mixed depressant were co-adsorbed on the calcite surface, while the H3Cit of the mixed depressant was weakly adsorbed on the scheelite surface. The mixed depressant can significantly improve the separation efficiency of scheelite from calcite. [ABSTRACT FROM AUTHOR]

The overuse of antibiotics can lead to the development of antibiotic-resistant bacteria, which can be even more difficult to treat and pose an even greater threat to public health. In order to address the issue of antibiotic-resistant bacteria, researchers currently are exploring alternative methods of sterilization that are both effective and sustainable. Polyoxometalates (POMs), as emerging transition metal oxide compounds, exhibit significant potential in various applications due to their remarkable tunable physical and chemical performance, especially in antibacterial fields. They constitute a diverse family of inorganic clusters, characterized by a wide array of composition, structures and charges. Presently, several studies indicated that POM-based composites have garnered extensive attention in the realms of the antibacterial field and may become promising materials for future medical applications. Moreover, this review will focus on exploring the antibacterial properties and mechanisms of different kinds of organic-inorganic hybrid POMs, POM-based composites, films and hydrogels with substantial bioactivity, while POM-based composites have the dual advantages of POMs and other materials. Additionally, the potential antimicrobial mechanisms have also been discussed, mainly encompassing cell wall/membrane disruption, intracellular material leakage, heightened intracellular reactive oxygen species (ROS) levels, and depletion of glutathione (GSH). These findings open up exciting possibilities for POMs as exemplary materials in the antibacterial arena and expand their prospective applications., Competing Interests: Declaration of competing interest The authors confirm that there are no financial or non-financial competitive interests that may affect the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)