Yanfei Fang,Peiyan Cheng,Xiangrong Li,Tingping Lei,Shaogan Ye
In water-lubricated conditions, surface modification techniques that enhance the formation of water-lubricating films through surface treatment play a significant role. This paper proposes a method of applying a modified epoxy resin coating on stainless steel to improve its tribological performance under water lubrication. First, nano-MoS₂-PEG6000 fillers were prepared via a hydrothermal method. They were uniformly mixed into the epoxy resin and coated onto the surfaces of stainless steel and slipper pairs. Tribological experiments were conducted using a slipper-on-disk configuration, followed by characterization. Experimental results demonstrate that the nano-MoS₂-PEG6000 modified epoxy resin coating exhibits excellent water-lubrication properties, with the friction coefficient reduced by 66.4 % and the wear rate decreased by 99.2 %. The mechanism was revealed: MoS₂ reduces the shear force between rough peak contacts, while PEG6000 possesses strong hydration capacity, forming a stable water-lubricating film on the surface, thereby reducing friction. This study provides a novel approach for the tribological design of slipper pairs in water hydraulic pumps.
Zeolitic imidazolate framework-8 (ZIF-8) nanoparticles loaded with polysaccharides are excellent drug-delivery carriers with high loading capacity and pH sensitivity. This study describes the one-step encapsulation of Dendrobium huoshanense polysaccharides (DHP) in ZIF-8. The resultant PEG6000/ZIF-8@DHP complex exhibited drug release properties in acidic microenvironments, possessed water solubility, demonstrated high drug loading capacity, and displayed effective encapsulation. The effects of PEG6000/ZIF-8@ DHP administration on immunoregulation, antioxidant activities, and resistance against Aeromonas veronii in channel catfish were assessed. The study revealed that the PEG6000/ZIF-8@DHP complex stimulated cellular proliferation and phagocytosis, while also inducing the production of cytokines and nitric oxide. Additionally, the complex exhibited improved antioxidant properties and increased serum lysozyme and alkaline phosphatase activities. PEG6000/ZIF-8@DHP exhibited efficacy in vivo against Aeromonas veronii infection. These results indicate that PEG6000/ZIF-8@DHP is an efficient immunostimulant and vaccine adjuvant for enhancing immunity in channel catfish.
In this work, the influence of polymeric excipients (PEG6000, PEG400, PVPK25, and HPMCE3) on thermodynamic phase behavior of active pharmaceutical ingredients (API) (mesalazine and allopurinol) and its aqueous solution was systematically investigated through experimental measurement and thermodynamic modeling. The API/excipients formulations were prepared by ball milling, and the phase behavior was measured by differential scanning calorimetry (DSC). The results showed that the solubility of API/solvent systems were all increased with higher temperature. Meanwhile, it was found that all four excipients can solubilize mesalazine and allopurinol effectively and the solubilization performance of PVPK25 and HPMCE3 were preferable to PEG. Furthermore, the thermodynamic phase behavior of API in the excipients/water ternary system was predicted by the Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT), demonstrating good accordance with the experimental results with low average relative deviations (ARDs). This work was expected to provide theoretical guidance for the screening of pharmaceutical formulation excipients.
危险品化学品经营许可证（带存储）