37 results about "Ferromagnetic nanoparticles" patented technology

This invention relates to a new type of reflective optical element made of a fluid that responds to a force if subjected to a magnetic field. As a consequence, one can impose any shape one wants to the reflecting surface by generating an appropriate magnetic field geometry with permanent magnets, electromagnets or a combination of permanent magnets and electromagnets, or the like. A preferred embodiment uses a ferromagnetic fluid made of water containing ferromagnetic nanoparticles. Liquid ferromagnetic surfaces thus obtained were successfully shaped using magnetic fields. In another preferred embodiment, to modify the reflectivity of the optical element, a reflective layer, such as a nano-engineered silver reflecting surface, is deposited on the surface of the magnetically sensitive fluid. The surface of the reflecting layer can therefore be warped by applying a magnetic field to the fluid. Coated or uncoated magnetically deformable liquid surfaces with reflective layers allows one to make inexpensive and versatile high-quality reflecting mirrors having complex shapes. The shapes of the reflecting surfaces can be changed within short time periods by changing the shapes of the magnetic fields.

An information recording apparatus comprises a plurality of fine particles forming an array on a plane in close proximity of each other, each of the plural particles including a ferromagnetic metal, a light-emitting device for exciting a near-field light, and a photo-electric conversion element for detecting a near-field light traveled along the fine particles.

A magnetic recording medium for high-density recording, having a doped interlayer to preserve the uniformity and ordering of the magnetic nanoparticles in its recording layer. The interlayer is doped with a high electronegativity material. The dopant atoms in the interlayer interact with the ferromagnetic nanoparticles to promote the formation of a homogeneous, ordered monolayer of nanoparticles in the recording layer. In addition, the high electronegative property of the dopant atoms holds the nanoparticles in place during the subsequent annealing process to prevent sintering and disordering damage. In one embodiment, the dopant is a halogen or non-halogen material having a high electronegativity, which is not polymerized to the matrix material in the interlayer. The matrix material may be polymerized. An example of a doped interlayer is a fluorinated carbon film.

The present invention relates to a water-soluble polymer complex that includes a water-soluble block copolymer and a magnetic nanoparticle, wherein the water-soluble polymer complex has a nonzero net magnetic moment in the absence of an applied magnetic field at ambient temperatures. The water-soluble block copolymer is preferably a diblock or triblock copolymer and the magnetic nanoparticle is preferably a ferrimagnetic or ferromagnetic nanoparticle. The water-soluble complexes may be derivatized with reactive groups and conjugated to biomolecules. Exemplary water-soluble polymer complexes covered under the scope of the invention include PEG112-b-PAA40 modified CoFe2O4; NH2-PEG112-b-PAA40 modified CoFe2O4; PNIPAM68-b-PAA28 modified CoFe2O4; and mPEG-b-PCL-b-PAA modified CoFe2O4.

The invention discloses a magnetic compound-cyanide decomposing enzyme composite nanoparticle, its preparation method and application, and a method for treating electroplating wastewater by using it. The raw materials for making the composite nanoparticle include: spinel ferromagnetic nanoparticle, magnetic oxide Nanoparticles, SiO 2 Nanoparticles, cyanide decomposing enzyme, first polymer compound, second polymer compound, silane, amine compound, nucleoside monophosphate disodium salt, first inorganic metal salt, second inorganic metal salt; The stone ferromagnet is modified by amino groups, by wrapping SiO 2 The magnetic oxide nanoparticles are modified by epoxy groups, and then the metal adsorption coupling is carried out through the first inorganic metal and the enzyme, which increases the way and amount of enzyme coupling, and stabilizes the enzyme activity and applicable pH range and temperature range. At the same time, the magnetic substance can be used to absorb heavy metal ions or dyes and achieve the effect of decomposing cyanide, reducing the amount of flocculant used and the amount of sludge after treatment.

The invention belongs to the field of nanometer materials, and specifically discloses a magnetic composite nanometer material, a preparation method and an application thereof. The raw materials for the preparation of the magnetic composite nanomaterial include Fe 3 o 4 Ferromagnetic nanoparticles, cellulose acetate and glyceryl trioleate, by modifying the surface of magnetic nanoparticles of cellulose acetate, and fixing glyceryl trioleate in the microporous structure of cellulose acetate; by controlling the ratio of solvent addition and temperature and other conditions, magnetic composite nanoparticles can be prepared. The preparation method of the magnetic composite nanomaterial is a chemical co-precipitation synthesis technology, which has the advantages of simple preparation process and equipment requirements, high stability of the produced material, and the obtained magnetic composite nanoparticle not only has a large specific surface area, but also has the advantages of being resistant to pollutants. The adsorption efficiency is fast, and it can be used for the adsorption of organic matter in sewage treatment; and there is less superparamagnetic interference to the material itself, and it can be quickly recovered under an external magnetic field, avoiding environmental pollution.

The invention discloses a low-temperature and low-pressure gas-phase preparation method of ferromagnetic chromium oxide nanoparticle film, which uses metal Cr as a precursor, through plasma gas-phase aggregation and real-time oxidation method, and utilizes the unique nucleation in the gas-phase aggregation process Growth and reaction environment, forming Cr oxide nanoparticles in the gas phase environment, and through the differential vacuum system, the formed nanoparticles are deposited on the substrate under high vacuum, forming a chromium oxide nanoparticle film at room temperature and low pressure, oxidation The main component of the material is chromium dioxide with ferromagnetism. The preparation method of the invention can be applied to the preparation process of high-density storage devices and nano-magnetic electronic devices, and has the characteristics of simple process, stability, high efficiency, easy scale and the like.

The invention relates to a preparation method of ferromagnetic nanoparticles grafted on surface of polyglycerol. Ferric oxalate pentahydrate is taken as a precursor compound, triethylene glycol is taken as a solvent, glycidol is taken as a surface modifier, the synthesis is performed through a one-pot process, and the method comprises the following steps: mixing an iron salt oxalate and the strongly polar high-boiling point solvent with a hydroxyl group, firstly reacting at the temperature of 200 DEG C for 1-10 hours, then reacting at the temperature of 280-350 DEG C for 1-10 hours, and naturally cooling to 25 DEG C-120 DEG C after the completion of the reaction; and then adding glycidol monomers, uniformly mixing, reacting at the temperature of 50-200 DEG C for 1-24 hours, then adding the polar organic solvent, precipitating, and separating obtained solids to get the ferromagnetic nanoparticles grafted on the surface of the polyglycerol. The preparation method disclosed by the invention has the advantages that compared with the two-step preparation of the ferromagnetic nanoparticles, the one-pot process preparation process is simple and easy to realize the large-scale industrial production; and the particle size of the ferromagnetic nanoparticles prepared by the method is 10-20nm, and the particle size distribution is uniform.