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Silver plating can be divided into replacement plating and electroplating.In order to compare the corrosion resistance and galvanic corrosion behavior of coatings prepared by these two methods，the corrosion resistance and galvanic corrosion behaviors of the ZHL-02 replacement plating and ZHL-02 electroplating coatings in cyanide-free silver plating process using 5，5-dimethylamide as the main complexing agent were analyzed by scanning electron microscopy，XRD，electrochemical workstation，Tafel curve and galvanic corrosion methods.Results showed that the replacement coating had better crystallization and more complete coverage，and its resistance to galvanic corrosion was slightly better than that of the electroplating coating under the same thickness.With the prolongation of replacement silver plating time，the self-corrosion rate of the coating gradually decreased.However，the replacement plating took a long time，and it was difficult to obtain a thickness of more than 1 μm，which limited its application to a certain extent.Compared with replacement plating，the plating speed of electroplating was much faster，the silver coating ＞2.4 μm could be obtained for 5 min.As the extension of electroplating time，larger particles would appear in the silver coating，forming defective structures such as tiny pores.When the electroplating silver times were 1，2，and 5 min，the corresponding self-corrosion rates were 7.15×10-3，5.30×10-3 and 4.27×10-3 mm/a respectively.Besides，when the electroplating time was extended from 1 min to 2 min and then to 5 min，the average galvanic corrosion rate of the coating decreased first and then increased.

Uniform acidizing has been an urgent challenge in strongly heterogeneous and high-temperature carbonate reservoirs. Nanoparticles have been shown to enhance the viscosity of viscoelastic-surfactant (VES) fracturing fluids, thereby improving the proppant carrying capacity of the fluid. However, there is almost no understanding of the nanoparticles on wormhole propagation and diversion in VES acid at low pH values and high salinity. Here, the rheological and adsorption model of nanoparticles in VES acid are established based on experimental results, and the multi-field and multi-scale coupling model of nanoparticles-VES acid is established by introducing the temperature field and two-scale continuum model. Based on the model, the propagation pattern and diverting performance of the wormholes were analyzed. The effects of permeability contrast, temperature, and adsorption on the propagation pattern and diverting performance are systematically investigated. The results show that the synergistic effect of nanoparticles and adsorption divided the invaded zone of spent acid into high-viscosity and low-viscosity zones, and the propagation capacity of the wormholes in the low-permeability reservoir was increased by 17%. The propagation and diverting process of wormholes can be divided into three stages. In stage II, when the additional resistance increased by spent acid is enough to resist the permeability contrast and the wormholes, more acid starts to flow into the low-permeability reservoir. The higher flow rate in the high-permeability reservoir makes the propagation path more complicated, and more branching wormholes are formed. At a reservoir temperature of 393 K, the nanoparticle-VES acid has the poor diverting ability for reservoirs with permeability contrast greater than ten. When the maximum adsorption capacity is 0.008 mol/kg, the diverting performance of nanoparticle-VES acid and VES acid were close. Reducing the adsorption is a very effective way to enhance the diverting performance. When the adsorption capacity is larger, the influence distance of the high viscosity zone formed by the dominant wormholes is limited, and the number of main wormholes in the reservoir becomes significantly large. This study clarifies the propagation law and diverting characteristics of wormholes using nanoparticle-VES acid, fills the technical gap of nanoparticles in acidizing, and provides guidance and a basis for the stimulation of uniform acidizing in high-temperature carbonate. [ABSTRACT FROM AUTHOR]