3results about How to "Restrict growth" patented technology

This invention discloses a method for controllable preparation of nanoparticles using a multi-channel microreactor. The method utilizes a microchannel reactor to segment droplets and prepare quantitatively synthesized nanoparticles with controllable particle size. The invention employs capillary action to draw the reaction solution into the microchannel, segmenting one or more droplets (each droplet into 10-100 portions). By changing the width of the microchannel, controllable preparation of nanoparticles within a small range (±3 nm) can be achieved; by changing the length of the microchannel, controllable preparation of nanoparticles within a large range (±10-30 nm) can be achieved. Furthermore, the reactor structure of this invention is simple, enabling highly precise and quantitative synthesis of various nanoparticles. Compared to large-scale reactors, the miniaturization of the synthesis reaction in this invention effectively reduces energy waste and safety hazards, making it highly valuable for applications in safe chemical engineering, green chemical engineering, high-efficiency chemical engineering, microchemical engineering, and precise reaction monitoring.

The utility model relates to the technical field of medical instruments, in particular to an absorbable valve support and a valve prosthesis comprising the absorbable valve support. The absorbable valve stent comprises an inner stent and an outer stent arranged on the peripheral side of the inner stent, the outer stent comprises a main body section and a valve ring section which are connected, the main body section is used for being matched with an atrium, the valve ring section is used for being matched with a valve ring, the bottom of the valve ring section is connected with the bottom of the inner stent through a connecting frame, and the main body section is composed of a first rod piece; the first rod piece is a non-completely absorbable rod piece or is integrally made of degradable absorption materials, and the non-completely absorbable rod piece comprises an inner core made of non-degradable absorption materials and an outer skin made of degradable absorption materials and wrapping the inner core. After implantation, the supporting force of the main body section to the atrium is weakened through degradation and absorption of the outer skin of the main body section, or the supporting force of the main body section to the atrium is relieved through complete degradation and absorption of the whole main body section, and the normal contractility of the atrium can be recovered.

The application belongs to the field of carbon monoxide treatment and catalytic oxidation in sintering flue gas, and discloses a preparation method and application of a ceria-supported bimetallic catalyst. A cerium source, a surfactant, a complexing agent and a crosslinking agent solution are mixed, and the pH is adjusted to make metal ions form hydroxide precipitates to obtain a precursor turbid solution. After hydrothermal reaction, the precursor turbid solution is filtered, washed, dried, ground and calcined to obtain a precursor powder. The precursor powder is dispersed, and a bimetallic solution is gradually added dropwise. The ceria-supported bimetallic catalyst is obtained through drying and calcination treatment. 3+ The surfactant, the complexing agent and the crosslinking agent are introduced to synergistically regulate Ce Hydrolysis, inhibit grain growth and construct three-dimensional network limited space, obtain small grain, large specific surface area, rich in defects of ceria carrier, make it uniform dispersion, enhance metal-support interaction, promote alloy phase or hetero-interface formation, so as to significantly improve the stability of catalytic active center, selectivity.