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Background. As a traditional Chinese medicine, rhubarb (also named Dahuang) is used to treat various diseases. Objective. To explore the possible antitumor mechanism of rhubarb by using network pharmacology and molecular docking in this study. Methods. Bioactive ingredients and related targets of rhubarb were obtained from the Traditional Chinese Medicine Systems Pharmacology (TCMSP) database. And the gene names corresponding to the proteins were found in the UniProt database. Then, the tumor-related targets were screened out from GeneCards and OMIM databases. Key antitumor targets of rhubarb were acquired by overlapping the above targets via the Venn diagram. The antitumor targets network of rhubarb active components was constructed by using Cytoscape 3.6.0 software. The protein interactions network was constructed using the STRING database. The GO and KEGG pathways involved in the targets were analyzed by using the DAVID database. Autodock Vina software was used to verify the molecular docking of rhubarb components and key targets. Results. Through screening and analysis, 10 active ingredients and 58 antitumor prediction targets were obtained and constructed a compound-target network. The targets such as CASP3, JUN, MYC, TNF, and PTGS2 may play a crucial role. These targets are involved in cancer pathway, calcium signaling pathway, cell apoptosis, small-cell lung cancer pathway, p53 signaling pathway, and TNF signaling pathway. The docking results indicated that the rhein binding with the CASP3 showed the highest binding energy. Conclusion. Based on the network pharmacology, the characteristics of multicomponent, multitarget, and multipathway of rhubarb were discussed, which provided a scientific basis for explaining the mechanism in treating cancer and new ideas for further research.

In this work, the structure and properties of ZrO2 nanoparticle reinforced Ni–W, Ni–B and Ni–Cu matrix nanocomposite coatings were comparatively studied. Their surface morphology, composition, microstructure, topography, hardness, wear and corrosion resistance were examined by various methods . The nanocomposites exhibit dense, nodular-like morphology with nanocrystalline structure. The results show that the ZrO2 particles have homogeneously dispersed in the nanocomposites. The formation of the protrusion structure was partly attributed to the heterogeneous distribution of the electric field. The presence of ZrO2 nanoparticles could refine the crystallite size of the Ni–W, Ni–B and Ni–Cu alloy matrix to 12.5 ± 1, 10.5 ± 0.5 and 15 ± 0.1 nm, respectively. The corrosion resistance of these nanocomposites can be improved by the incorporation of ZrO2 nanoparticles into the alloy matrix. The R a of Ni–W/ZrO2, Ni–B/ZrO2 and Ni–Cu/ZrO2 nanocomposites are about 53 ± 3, 69 ± 2, 18 ± 1 nm, respectively, expressing the rougher surface of Ni–B/ZrO2 compared to the others. It indicated that the composition of these alloy matrix have different crystallite size, which could affect the surface roughness of the electrodeposits. The inclusion of ZrO2 particles in Ni-based alloys could enhance its properties. The reinforcement effect of the anti-wear properties of the nanocomposites was proposed. The R ct value of the Ni–W–ZrO2, Ni–B–ZrO2, Ni–Cu–ZrO2 were 50.93, 105.18, 44.67 kΩ · cm2, respectively, indicating that the Ni–B–ZrO2 nanocomposite coating has the highest corrosion resistance. The R ct values depends on not only the composition of the coatings, but also the electrodeposition conditions, which influence the crystallize size and compactness of the electrodeposits. The order of the microhardness and anti-wear properties is Ni–W–ZrO2 > Ni–B–ZrO2 > Ni–Cu–ZrO2.

The effects of ZrO2, TiN, BN and Si3N4 nanoparticles on the microstructural, surface characteristics and properties of Ni-W composite coating have been comparatively studied in this paper. Their morphology, microstructure and characteristics were evaluated. Results illustrated that nanoparticles have been distributed in Ni-W composite coating, which could reinforce their properties. The surface topography was affected by the operating parameters. The formation of nodular protrusions could be attributed to the preferential discharge of the metal ions at the raised sites. The incorporation of nanoparticles could refine grains. The crystallite size of ZrO2, TiN, BN, and Si3N4 reinforced Ni-W composite coating were 13 ± 1, 13 ± 2, 12 ± 1 and 18 ± 1 nm, respectively. The roughness values (R a) of ZrO2, TiN, BN and Si3N4 strengthened Ni-W composite coating is about 50 ± 2, 70 ± 4, 89 ± 11 and 25 ± 1 nm, respectively. The corrosion-resistant and anti-wear capability have been enhanced by incorporating nanoparticles into the Ni-W alloy matrix. The strengthening mechanisms of the nanocomposite coating were proposed. These nanocomposite coating exhibit potential application advantages as protective coating with high performance in harsh conditions.

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