8 results about "Displacement reactions" patented technology

The application discloses an intermediate processing liquid for an electroless nickel immersion gold (ENIG) production line and a chemical gold preparation method. The intermediate processing liquid is applied between the electroless nickel plating and immersion gold processes, and comprises (a) a pH buffer and a metal ion complexing agent: a total concentration of 50-150 g / L; (b) an adsorptive corrosion inhibitor: a concentration of 0.5-5.0 g / L; (c) a low-foam non-ionic surfactant: a concentration of 0.01-10 g / L; (d) an auxiliary antioxidant: a concentration of 0.5-30 g / L; (e) a dissolving agent: a concentration of 1-50 ml / L; (f) a pH regulator: an appropriate amount, which is added to maintain the pH value of the intermediate processing liquid at 4.0-6.5; and (g) deionized water: a balance, so that the concentrations of the above components reach the set target values; and the intermediate processing liquid has a design use temperature of 20-45 DEG C. The intermediate processing liquid removes residual nickel ions on the board surface and in micropores through strong complex cleaning, and blocks the pollution to the subsequent gold tank; meanwhile, the preferential adsorption of the corrosion inhibitor molecules at the nickel layer grain boundaries forms a controllable molecular-level protective film, effectively adjusts the immersion gold replacement reaction kinetics, and prevents the occurrence of intergranular corrosion (black plate).

This invention discloses a method for preparing high-purity terbium-iron alloy, utilizing ferric fluoride as a chemical decalcification agent in the refining stage. Compared with existing technologies that rely solely on high-temperature volatilization and physical adsorption for calcium removal, this method provides a clear chemical driving force, converting calcium dissolved in the alloy melt into an insoluble calcium fluoride slag phase through a displacement reaction, thereby achieving efficient calcium removal. This invention can reduce the calcium content in terbium-iron alloy from 0.011-0.015% in traditional processes to 0.002-0.004%, a reduction of 70-85%. This method requires no special equipment; only the addition of ferric fluoride in the refining stage is needed, resulting in low process modification costs and good industrial applicability.

The purpose of this invention is to provide a carbon framework supported and embedded Ni3ZnC 0.7 This paper describes the preparation method and application of NiPt1 single-atom alloy catalysts, belonging to the field of functional materials technology. Using a core-shell structure ZIF-8@Ni-MOF as a precursor, porous carbon-supported Ni3ZnC catalysts are prepared by controlling the pyrolysis temperature, time, and Zn / Ni molar ratio. 0.7 Ni particles; Pt single atoms are anchored in situ using current displacement to form a supported single-atom alloy catalyst. Because Pt 4+ with Ni 0 A current displacement reaction occurs, causing Ni nanoparticles to be etched into small nanoclusters, while simultaneously anchoring Pt single atoms to their surface, thus producing a Ni3ZnC coating. 0.7 The outer layer is a NiPt1 single-atom alloy. Ni3ZnC 0.7 The tunable electronic structure of Ni can alleviate OH blockage and lower the water dissociation energy barrier, providing a new pathway for the development of highly efficient alkaline HER catalysts.

Disclosed in the present invention is a preparation method, comprising the following steps: S1. preparing a salt solution of metal A ions and a solution containing elemental metal B particles, the reducing ability of metal B being greater than the reducing ability of metal A; and S2. simultaneously introducing the salt solution of metal A ions and the solution containing elemental metal B particles into a reaction vessel, while synchronously applying a negative pressure to the reaction vessel, so that the salt solution of metal A ions and the solution containing elemental metal B particles both form a turbulent flow state within the reaction vessel, and performing a displacement reaction, such that surface atoms of the elemental metal B particles are replaced by elemental nanoscale metal A, thereby forming a multiphase composite core-shell material, so as to obtain a metallization slurry for a package substrate. The preparation method for a metallization slurry for a package substrate proposed by the present invention is beneficial for simplifying a preparation process, improving production efficiency, and facilitating industrial-scale production, while ensuring the uniformity of the obtained multiphase composite core-shell material, thereby ensuring the stability of the performance of the metallization slurry.

This invention belongs to the field of oil extraction and relates to a method for characterizing the breakthrough point of bio-nano-based unblocking and injection enhancement. The method includes: measuring the porosity and permeability of the core sample; injecting a bio-nano-based unblocking agent using KCl or NH4Cl solution for displacement, and analyzing the breakthrough point of the bio-nano-based unblocking agent; flushing the pipeline with simulated formation water, shutting off the displacement device, injecting the bio-nano-based injection enhancement agent, and measuring the porosity and permeability of the core sample again; dividing the unblocking process into a linear flow model into contaminated and uncontaminated zones, determining the contaminated skin coefficient based on Darcy's formula and the definition of the skin factor, and determining the fluid viscosity in the contaminated zone and the fluid viscosity in the uncontaminated zone at any given time; deriving the relationship between pressure difference and time during the core displacement reaction process based on the fitting relationship between pressure difference and the rising and falling phases of the injected PV number, and the relationship between the unblocking agent propulsion time and the injected PV number; and determining the relationship between fluid viscosity and the unblocking agent injection time based on the relationship between pressure difference and time during the core displacement reaction process.

This invention provides an apparatus for recovering copper from waste ionic liquids, comprising: a displacement reactor and a sedimentation tank. The displacement reactor includes, from bottom to top, a water and gas distribution zone, a displacement reaction zone, a three-phase separation zone, and an effluent zone, all connected sequentially. The effluent zone surrounds the upper part of the three-phase separation zone. The water and gas distribution zone is provided with a reactor inlet and a reactor gas inlet. The displacement reaction zone includes, from bottom to top, a support layer and an aluminum particle layer. The three-phase separation zone is provided with a three-phase separator, the aqueous phase outlet of which is connected to the effluent zone. The effluent zone is connected to the sedimentation tank, and the sedimentation tank is provided with a sedimentation tank outlet, a circulating water outlet, and a sedimentation outlet at its upper, middle, and bottom parts, respectively. This invention also provides a method for recovering copper from waste ionic liquids. This apparatus is space-saving, has a high copper displacement recovery rate, strong shock resistance, and can effectively recover copper resources and reduce wastewater treatment costs, showing broad application prospects.

The application provides a gold nanoflower SERS substrate and a preparation method and application thereof, the preparation method removes the surface oxide film of an aluminum foil by using an etching solution, and realizes in-situ growth of the gold nanoflower on the surface of the aluminum foil by combining with a spontaneous displacement reaction of chloroauric acid. The preparation process is simple to operate, does not need an external power supply, raw materials are easy to obtain, and the cost is low; in addition, the substrate can be prepared in a large area, and the problems of a traditional SERS substrate, such as complicated process, high cost and difficulty in large-scale production, are effectively solved. The prepared substrate has a multi-stage rough microstructure, a high-density and uniformly-distributed SERS hot spot is formed on the surface, and the Raman signal enhancement effect is excellent. The substrate does not need sample labeling and substrate surface modification, and can quickly complete Raman spectrum detection of pseudomonas aeruginosa; in addition, the five types of carbapenemases can be accurately identified, and the detection process is efficient, and the result is stable and reliable.

The present disclosure describes in detail a polymerase-free, isothermal method for detecting nucleotide sequences. The method uses a target-specific hairpin oligonucleotide that also specifically interacts with a probe labeled with a fluorescent dye and a quenching group, amplifying detection of the target polynucleotide through repeated cycles of endonuclease-mediated probe cleavage to drive dissociation of the fluorophore-labeled probe fragment from the hairpin-probe complex, thereby separating the fluorescent label from the quencher.