30results about How to "Electromagnetic Field Enhancement" patented technology

The invention provides a hydrogenation method for silicon tetrachloride, and belongs to the technical field of polycrystalline silicon production. The hydrogenation method for silicon tetrachloride ischaracterized in that silicon tetrachloride and hydrogen are introduced into a gas discharge reactor filled with an electromagnetic field adjusting material and a supported metal catalyst, and a reaction is performed under the action of the electromagnetic field. The method can improve the low-temperature hydrogenation efficiency of the silicon tetrachloride and reduce the temperature of a reaction system.

The invention belongs to the field of chemical engineering, and provides a preparation method for special-shaped gold nanocrystals and application on detection of tripolycyanamide by using surface enhanced Raman scattering. The preparation method comprises the following steps of preparing gold by using trisodium citrate as a stabilizer; using hexadecyl trimethyl ammonium bromide, a chloroauric acid, silver-bearing salt liquor and an ascorbic acid as growth-promoting media; preparing nanogold by using an organic acid as an additive; and performing resolution after centrifugal separation. The special-shaped gold nanocrystals are used for detecting Raman spectra of standard liquor or sample liquor of the tripolycyanamide. The nanogold is prepared by using a seed induction multi-step growing method, an additive containing benzene ring is added in the nanogold, and the use level of the hexadecyl trimethyl ammonium bromide is reduced, so that the cost is obviously reduced, and purification time and purification steps are reduced. The prepared nanogold has an angular structure, and can be used for detecting an enhancement substrate of trace tripolycayanamide by using surface enhanced Raman scattering; and compared with an HPLC (high performance liquid chromatography) method, the nanogold has the advantages that the analyzing time is short, the cost and the reproducibility are high, and the nanogold can be widely applied to quickly detecting the tripolycyanamide in dairy products.

The invention discloses a gold nanoparticle-silver nano-semisphere array as well as a preparation method and the application of the array. The array is an ordered array which is placed on a silver membrane of a substrate and attached with silver nano-semispheres, wherein the sphere diameter of the silver nano-semisphere is 85-95 nm; the sphere interval is less than or equal to 10 nm; the gold nanoparticles are modified on the silver nano-semispheres; the particle size of the gold nanoparticle is 5-10 nm. The preparation method comprises the following steps: sequentially performing secondary anodic oxidation, reaming treatment and silver membrane plating on one side of an aluminum sheet, so as to obtain an aluminum oxide template covered with the silver membrane on one side and collected with the silver nano-semispheres in the hole; adhering and fixing the substrate to the silver membrane; then, placing the aluminum oxide template covered with the silver membrane and the substrate on one side and collected with the silver nano-semispheres in the hole in an alkali solution to etch off the aluminum oxide template, and then putting the rest in an ion sputtering device to perform gold sputtering for 8-12 s under the sputtering current is 35-45 mA, so as to obtain the objective product. The array can be taken as an active substrate for enhancing raman scattering on the surface, so that the content of trace rhodamine or polychlorinated biphenyl 3 attached on the array can be measured by a laser raman spectrometer.

The invention provides a nucleic acid nanostructure and its preparation method and application. The nucleic acid nanostructure is a hexagonal DNA nanostructure formed by assembling six triangular DNA origami structures constructed by DNA origami technology, specifically through scaffolding chains and The staple strand and the capture strand are hybridized, and the hexagonal DNA nanostructure is self-assembled by hybridizing the connecting strands with the scaffold strands of the six triangular DNA origami structures. The nucleic acid nanostructure has good stability and can anchor two 80nm gold triangular prisms, and the prepared gold bowtie structure can generate a strong electromagnetic field, realizing single-molecule Raman detection.