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Förster resonance energy transfer (FRET) has been essential for many applications, in which an appropriate donor-acceptor pair is the key. Traditional dye-to-dye combinations remain the working horses but are rather nonspecifically susceptive to environmental factors (such as ionic strength, pH, oxygen, etc.). Besides, to obtain desired selectivity, functionalization of the donor or acceptor is essential but usually tedious. Herein, we present fluorescent poly(m-aminophenylboronic acid) nanoparticles (poly(mAPBA) NPs) synthesized via a simple procedure and demonstrate a FRET scheme with suppressed environmental effects for the selective sensing of cis-diol biomolecules. The NPs exhibited stable fluorescence properties, resistance to environmental factors, and a Förster distance comparable size, making them ideal donor for FRET applications. By using poly(mAPBA) NPs and adenosine 5'-monophosphate modified graphene oxide (AMP-GO) as a donor and an acceptor, respectively, an environmental effects-suppressed boronate affinity-mediated FRET system was established. The fluorescence of poly(mAPBA) NPs was quenched by AMP-GO while it was restored when a competing cis-diol compounds was present. The FRET system exhibited excellent selectivity and improved sensitivity toward cis-diol compounds. Quantitative inhibition assay of glucose in human serum was demonstrated. As many cis-diol compounds such as sugars and glycoproteins are biologically and clinically significant, the FRET scheme presented herein could find more promising applications.

The influences of Hexagonal boron nitride (hBN) and Calcium carbonate (CaCO3) nanoparticles on tribological and bearing vibration properties of polyurea grease (PG) were investigated. The microstructure, friction coefficient, wear morphology, and bearing vibration test of five components of greases were conducted. The results showed that the addition of 1 wt% hBN, playing the role of isolation protection and nano-abrasive, could improve the wear and vibration reduction performance of PG. However, the addition of CaCO3 nanoparticles at the same time, playing the role of deposition and recovery, could further improve the tribological and vibration reduction performance of PG, which was attributed to the synergistic effect of CaCO3 and hBN particles. The findings revealed that PG with the addition of 1 wt% hBN + 5 wt% CaCO3 nanoparticles had the greatest tribological and vibration suppression performance, which is due to the synergistic effect of hBN and CaCO3 nanoparticles. Additionally, the wettability tests showed that the addition of hBN and CaCO3 nanoparticles could significantly increase the flow of base oil on the PG soap fibers, resulting in the most effective bearing vibration suppression. [ABSTRACT FROM AUTHOR]

Wood has excellent properties such as biodegradability, high reactivity and rich channel skeleton structure. However, the defects such as hole blockage and limited specific surface area limit the application of wood-based materials in wastewater treatment. Therefore, in this research, wood substrates (DTWS) were treated using a deep eutectic solvent method, which was able to remove both lignin and hemicellulose from wood. Wood-based carriers with high specific surface area and high chemical activity were formed. The DTWS-Ag material was formed by growing Ag nanoparticles (NPs) in wood channels by hydrothermal method. The results showed that with the increase of lignin and hemicellulose removal, the degradation performance of DTWS-Ag material showed a volcanic trend due to the interaction between Ag and the inner wall of the pipe. The pore size and the amount of Ag NPs are very important to the degradation rate of dye molecules. DTWS-4-Ag composite material makes wood pore diameter and Ag NPs production reach a high balance, so that it has the highest degree of reduction. DTWS-4-Ag showed high catalytic degradation efficiency and stability for methylene blue degradation, with the degradation efficiency up to 98.3 %. This low-cost, renewable wood-based filter has high dye degradation efficiency and can be widely used in practical wastewater treatment. [Display omitted] • DTWS-Ag membranes modified by low eutectic solvent method were prepared. • Partial removal of lignin and hemicellulose improves degradation efficiency. • Catalytic activity of material was inhibited by excessive removal of components. • The membrane showed good removal of highly concentrated dye solutions. [ABSTRACT FROM AUTHOR]

The surface microstructure of biomimetic Procambarus clarkia claw was prepared on the surface of GCr15 steel, then PTFE solid lubricants dispersed with three different hardness nanoparticles (C, ZnO, Al 2 O 3) were filled in. The results of the tribological experiment show the textured surface lubricated by PTFE with Al 2 O 3 nanoparticles reflected the best performances. Because PTFE stored by the bionic texture could be supplied to the friction surface to form a solid lubrication film. Due to the addition of Al 2 O 3 nanoparticles, the hardness and wear resistance of the film are improved, thus avoiding a large loss of PTFE. And the process of "rolling-embedding PTFE surface-exposing-rolling" occurs. As a final, the surface tribological properties of GCr15 steel can be significantly improved. • The PTFE could be supplied to the friction surface to form a solid lubrication film. • The Al 2 O 3 nano-particles enhance hardness and wear resistance of lubricant film. • The textured surface lubricated by PTFE with Al 2 O 3 reflected the best performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • ZnO@SiO 2 have better dispersion in lubricants than ZnO/SiO2 mixed nanoparticles. • ZnO@SiO 2 composite nanoparticles can form a stable tribo-film on the worn surface. • SiO 2 shell absorb long chain molecule of base oil, forming a high viscosity layer. Nano additives have been widely proven to significantly improve the tribological properties of traditional greases, and the synergistic effect of multiple nanomaterials to improve the performance of greases is a promising research direction. In this paper, based on the hardness of the bearing material GCr15 steel, harder SiO 2 nanoparticles and softer ZnO nanoparticles were selected to synthesize hard-shelled soft-core composite nanoparticles (ZnO@SiO 2) by chemical deposition, and it was used as grease additive for the first time. The composite ZnO@SiO 2 nanoparticles have better dispersion and tribological properties than the physically mixed nanoparticles (ZnO/SiO 2). When 1 wt% ZnO@SiO 2 was added to the grease, the coefficient of friction and wear scar diameter were reduced by 11.5% and 25%, respectively. The special hard-shell-soft-core structure of the composite not only has good dispersion, but also forms a special solid friction film on the surface of the friction pairs. The SiO 2 shell can absorb a large number of long-chain lubricant molecules and increase the viscosity of the lubricant in the friction zone, thus forming a solid-liquid phase composite lubricating film, which plays a significant role in friction reduction and anti-wear. [ABSTRACT FROM AUTHOR]

This paper presents a comparative study of the tribological and vibration performance of the synthesized lithium complex grease (LCG) containing Carbon black, Fe 3 O 4 and Al 2 O 3 nanoparticles on rolling bearing. The micromorphology, friction coefficient, worn surface and bearing vibration experiment of four greases were studied. The results show that in presence of nanoparticles friction and wear behaviors are improved compared to LCG without nanoparticles. The best tribological performance is obtained in presence of Al 2 O 3 nanoparticle, which is mainly attributed to its high hardness, cylindrical shape and deposition on the worn surface. Further, the wettability test shows that Al 2 O 3 nanoparticles can effectively promote the flow of base oil on the LCG soap fibers, which results in the most effective bearing vibration suppression. • The Al 2 O 3 nano-particles have the largest hardness and show cylindrical microscopic morphology. • The Al 2 O 3 nano-particles were intensively deposited on the surface of worn steel ball. • The Al 2 O 3 nanoparticles effectively promote the flow of base oil on the LCG soap fibers. [ABSTRACT FROM AUTHOR]

To evaluate the effects of CuO nanoparticles on friction and vibration behaviors of grease on rolling bearing, lithium complex grease (LCG), polyurea grease (PG), calcium sulfonate complex grease (CSCG) and these three greases containing 1 wt% CuO nanoparticles were prepared respectively. The microstructure, friction coefficient, wear surface and bearing vibration test of six greases were investigated in detail. The results show tribological properties of PG are improved most significantly, with the friction coefficient and wear scar diameter decrease, and the wear surface is fine and smooth. This is mainly attributed to the synergistic effect of lamellar thickener structure and CuO nanoparticles. Further, the addition of CuO nanoparticles to PG also has an obvious inhibitory effect on bearing vibration. • The three thickeners show coiled fibrous, lamellar and reticular microstructure. • The CuO nanoparticles have different effects on friction of the three greases. • The CuO nanoparticles affect the vibration of bearing with three greases. [ABSTRACT FROM AUTHOR]