114results about "Diamagnetic/paramagnetic materials" patented technology

The invention belongs to the field of preparing a nanomaterial, and particularly relates to a magnetic fluorescent double-function nanoion probe and a preparation method thereof. The composite microparticles have the fluorescent performance of quantum dots and the magnetism performance of magnetic nanoparticles, and can be used as target positioning in biological body and biological fluorescent imaging aspects. The invention provides a preparation method of the magnetic fluorescent double-function nanomaterial, and the magnetic fluorescent double-function nanomaterial is obtained by taking chitosan-modified magnetic nanoparticles as a core and connecting water-soluble quantum dots through adopting an ionic crosslinked method, the fluorescent quantum dots are distributed on the surfaces of the magnetic nanoparticles with the particle size of 10-200nm, and the particle size of the quantum dots is 1.5-10nm. The preparation method is mild in reaction conditions, the operation method is simple, the prepared composite nanoparticles have good luminescence performance and magnetic performance, and have wide application prospects in the fields of biomarking, fluorescent immunoassay, bioseparation, protein DNA enrichment and separation, the preparation of drug carrying system, and target imaging and the like.

The invention provides a method for preparing a nanocomposite material by assembling ferriferrous oxide in a halloysite tube, and belongs to the technical field of deep processing of nonmetallic minerals. The method comprises the following four steps: (1) pretreatment, tube expansion and purification of the halloysite minerals; (2) modification in the halloysite tube; (2) preparation of Fe3O4 magnetic nanoparticles through a mixed hydrothermal solution technology; and (4) vacuum impregnation for obtaining the compoiste material with the nano-Fe3O4 assembled in the halloysite tube. The halloysite/Fe3O4 composite material prepared in the invention has no residual magnetization or coercive force, and has a typical paramagnetic performance. The material prepared through the method has good biocompatibility, and broadens the application prospect of mineral magnetic materials in the fields of biomedicines and composite magnetic materials.

A method of stabilizing electromagnetically charged particles, which includes coating electromagnetically charged particles with a protective layer; and etching the protective layer to produce a porous protective layer on the electromagnetically charged.

The invention relates to a preparation method of superparamagnetic cyclodextrin composite particles. The preparation method comprises the following steps: firstly preparing a magnetic nanometer particle mixed system, and then, adding cyclodextrin powder; adding the cyclodextrin powder to the obtained magnetic nanometer particle mixed system containing a small amount of water and adjusting the pH value of the magnetic nanometer particle mixed system to be larger than 10 by an aqueous alkali; dispersing the cyclodextrin powder under ultrasound for 5-30 minutes so as to dissolve cyclodextrin; and obtaining the superparamagnetic cyclodextrin composite particles by compounding, increasing the temperature of the reaction system to 40-80 DEG C, fully stirring the reaction system and reacting for 3-20 hours before ending, and magnetically separating and centrifugating or dialyzing the system to be neutral so as to obtain the magnetic cyclodextrin composite particles. The invention aims to utilize active groups of the cyclodextrin and the magnetic nanometer particles and does not need adding a coupling reagent so as to be directly compounded into the magnetic composite particles which have high biological compatibility and saturation magnetization intensity and can slowly release a plurality of medicaments.

A reusable composite paramagnetic particle may comprise a paramagnetic core encased by a protective material to which is grafted a tendril layer comprising a plurality of polymeric chains. The polymeric chains may be designed to interact with a microorganism. The interaction between the microorganism and the polymeric chain may be electrostatic. The nanoparticle may be used in a method to isolate or recover microorganisms from solutions using an externally applied magnetic field.

The present invention is related to gold or silver powder characterized by having paramagnetism. The gold or silver powder according to the present invention is a paramagnetic gold or silver powder having magnetism in the same direction as that of the external magnetic field in all temperature ranges. The paramagnetic gold or silver powder according to the present invention shows an extremely small coercive force, has no surface oxidation layers, is stable at a room temperature, has no cohesive property, and is highly dispersible.

The invention discloses hydroxyapatite powder with up-conversion fluorescence and superparamagnetism and a preparation method thereof. The preparation method adopts a step-by-step hydrothermal synthesis technology and specifically comprises the following steps: step 1, preparing hydroxyapatite powder HA:Ln1+Ln2 rich in two or more rare earth ions and up-conversion fluorescence with adjustable luminous color by hydrothermal synthesis; and step 2, performing hydrothermal reaction to realize exchange between iron ions and HA crystal surface cations (Ca<2+> and/or Ln<3+>) so as to obtain HA:Ln1+Ln2/Fe powder with superparamagnetism. The obtained hydroxyapatite powder has high up-conversion fluorescence intensity and strong penetrability under the excitation of near infrared light and can avoidtissue autofluorescence interference; and furthermore, the obtained hydroxyapatite powder has superparamagnetism under the action of an external magnetic field, thereby being favorable for promotingcell proliferation and osteogenesis. The hydroxyapatite powder has wide application prospects in the aspects of biomedicine fundamental research, development of high-performance bone and tooth repairmaterials, osteogenesis promotion, in vivo tracing research of biological materials, and the like.

The invention is directed to hydrophilic and hydrophobic superparamagnetic nanoparticles and their use as contrast agents for NMR including agents that distinguish oil and water in NMR logging of geological formations containing oil or water. Methods of making these SPIONs are also described.

The invention discloses a preparation method for a single-layer coated water-soluble superparamagnetic ferroferric oxide nano-particle and belongs to the technical field of nanometer materials and bioengineering. The method comprises the following steps: firstly, adopting a high-temperature pyrolytic process for compounding the superparamagnetic ferroferric oxide nano-particle and using multi-bond polymer with a large quantity of carboxyl groups for modifying the surface of the oil-soluble nano-particle, thereby acquiring the water-soluble ferroferric oxide nano-particle with water solubility and dynamic radius only increasing by 1-2nm. The modified magnetic nano-particle has uniform shape, excellent dispersity and high biocompatibility. The preparation method has the advantages of simple and feasible operation, high repeatability, and the like; the prepared water-soluble superparamagnetic ferroferric oxide nano-particle has a better imaging effect; the special groups on the surface thereof can be conveniently combined with the other biotic factors; a basis is established for the application of the nano-particle in the biomedicine fields, such as, magnetic resonance imaging, drug magnetic targeting transferring, magnetic thermal therapy, magnetic separation, and the like.

The invention relates to a preparation method of a CNTs/NiFe3O4 functional material, and belongs to the technical field of functional nano composite materials and environmental biology. The preparation method of the CNTs/NiFe3O4 functional material comprises the following specific steps: purifying and activating multiwalled carbon nanotubes; preparing CNTsFe3O4: preparing the CNTs/NiFe3O4 nano composite material. The CNTs/NiFe3O4 functional material prepared by the invention is used as an efficient biological catalytic material and a wave-absorbing material, has the characteristics of promoting oxidation-reduction reaction and electron transfer, is used as a stabilizer and a catalyst in sewage treatment anaerobic digestion reaction, can improve the methane yield and produce biomass energy,can play a role once being added, and has a good application prospect. The catalyst is good in dispersity in a reactor and uniform and consistent in reaction, and can be recycled to save the cost.

The invention provides a magnetic nano composite and a preparation method and an application thereof; the polymer-coated Fe3O4/SiO2 magnetic nano composite has a multi-shell type structure, and Fe3O4/SiO2 is dispersed in a pyrrole and thiophene copolymer substrate. The synthesis method comprises that a Fenton-like reagent (FeCl3+H2O2) is used as an oxidant, a chemical oxidation method is adopted, an aqueous solution is used as a reaction medium, and the novel pyrrole and thiophene copolymer-coated Fe3O4/SiO2 magnetic nano composite Fe3O4/SiO2/cPPyTh is synthesized; the synthesis method is simple and environmentally friendly. The Fe3O4/SiO2/cPPyTh magnetic nano composite has the surface containing N and S, has the advantages of superparamagnetism, relatively high magnetic responsiveness, relatively large specific surface area and relatively good acid resistance, and has excellent adsorption performance and quite high selective separation efficiency on gold ions.

The invention discloses modified nano iron oxide particles and application thereof in anaerobic fermentation. The modified nano iron oxide particles are obtained by surface modification of bare core magnetic nano iron oxide particles, and the modified iron oxide particles have different types of charges. A small amount of the modified iron oxide particles are added to an anaerobic system, and thenanoparticles can promote syntrophism of acidogenic bacteria and methanogenic bacteria to further increase electron transfer, promote the conversion of organic acids to methane generation paths, improve the buffering capacity of the system, increase the stability of the system, and further greatly improve the methane yield.

A method and apparatus is provided for generating an artificial heat sink below ambient temperature for a cryogenic condenser (32) by isothermally magnetizing a paramagnetic fluid and removing the magnetic field thereby creating a temperature drop in the fluid by the magentocaloric effect. The heat of magnetization is converted into mechanical work by initially placing the fluid inside a sealed chamber with a door (76) that opens to a conduit leading into the bore of a superconducting solenoid (72). When the solenoid (72) is energized with current, it creates a strong axial magnetic field that exerts magnetic attractive forces on the fluid inside the chamber. When the fluid is released by opening the door (76), it is accelerated through the conduit (70) toward the superconducting solenoid where it becomes magnetized by the increasing strength of the magnetic field. By mounting a non-magnetic turbine (120) inside the conduit between the solenoid and the chamber, the kinetic energy of the accelerating flow stream, which is equal to the heat of magnetization, is converted into mechanical work thereby achieving isothermal magnetization. By removing the magnetic field after the fluid enters the bore of the solenoid, a temperature reduction is achieved thereby enabling the fluid to absorb heat in a cryogenic condenser.

The invention relates to the technical field of functionalized magnetic nano materials, and provides a composite magnetic nano material based on DNA tetrahedrons, preparation and application. The preparation method comprises the following steps of synthesizing DNA tetrahedrons through a self-assembly reaction of a DNA single chain, loading magnetic nano particles on the surface of molybdenum disulfide particles, modifying gold nanoparticles on exposed active sulfur atoms of molybdenum disulfide particles, modifying the DNA tetrahedrons on the gold nanoparticles, and incubating and connecting protein antibodies on the DNA tetrahedrons. The material prepared by adopting the preparation method is used for enriching and detecting the low-abundance protein in the serum, the specific low-abundance protein in the serum can be efficiently and highly selectively enriched through a specific reaction between an antigen and an antibody, and the material takes a magnetic nano material as a matrix, so that the material has the advantages of simplicity, convenience and rapidness in use, the treatment time of the serum complex matrix is greatly shortened, and high-efficiency and high-selectivity enrichment of low-abundance proteins in the complex matrix can be realized.

Thermally annealed superparamagnetic core shell nanoparticles of an iron oxide core and a silicon dioxide shell having high magnetic saturation are provided. A magnetic core of high magnetic moment obtained by compression sintering the thermally annealed superparamagnetic core shell nanoparticles is also provided. The magnetic core has little core loss due to hysteresis or eddy current flow.

The invention discloses a type of emulsion based on magnetic particles and a preparation method thereof. The magnetic particle emulsion is prepared through oil and water emulsification by taking dendrimer modified magnetic ferroferric oxide particles as an emulsifier. By introducing an external magnetic field, the emulsion can be quickly demulsified under magnetic response and cyclically emulsified and demulsified. The method has the advantages of simple operation, low consumption of magnetic particles, low cost, reusability and green environmental protection.

Core shell nanoparticles of an iron oxide core, a silicon dioxide shell and an iron silicate interface between the core and the shell are provided. The magnetic properties of the nanoparticles are tunable by control of the iron silicate interface thickness. A magnetic core of high magnetic moment obtained by compression sintering the thermally annealed superparamagnetic core shell nanoparticles is also provided. The magnetic core has little core loss due to hysteresis or eddy current flow.

The invention relates to a magnetic iron oxide-graphene nano composite material for removing dye pollution of a water body as well as a preparation method and application of the magnetic iron oxide-graphene nano composite material. The preparation method comprises the following steps: dispersing graphene oxide into deionized water, adding the graphene oxide into a mixed solution of ferric chlorideand sodium citrate, fully mixing, regulating the pH value to 9-11, transferring into a reaction kettle, and carrying out hydrothermal reaction so as to obtain a gamma-Fe2O3@rGO nano composite material. Compared with the prior art, according to the gamma-Fe2O3@rGO nano composite material disclosed by the invention, gamma-Fe2O3 is uniformly distributed on the surface of the GO; and an interlayer composite structure formed by the gamma-Fe2O3 and the GO is beneficial to maintaining the stability of the material, and has the inherent characteristics of graphene and magnetic iron oxide nanoparticles, so that the composite material has a larger specific surface area and better adsorption performance, and has the necessity and feasibility of recycling.

The invention provides a preparation method of high-saturation magnetization superparamagnetic ferrite porous microspheres. The preparation method specifically comprises the following steps: synthesizing superparamagnetic ferrite microspheres and synthesizing superparamagnetic ferrite porous microspheres: synthesizing ferrite microspheres with good dispersity in one step by adopting a solvothermalmethod, and then etching monodisperse ferrite microspheres into a porous structure by adopting an etching method, so as to increase the specific surface area of the monodisperse ferrite microspheres.The superparamagnetic ferrite particles obtained by adopting the method maintain superparamagnetism, have high saturation magnetization and high adsorption capacity, and can be applied to the biological fields of drug delivery, targeted drug delivery, biological separation and the like. The method also has the advantages that the raw materials are green and non-toxic, each step of the method is simple and convenient to operate and pollution-free, and feasibility is provided for later industrial production.

The invention discloses a preparation method of a hedgehog-shaped magnetic microsphere. The method is based on magnetic nano particles wrapped by silicon dioxide, a silicon dioxide layer is used as a template, the silicon dioxide layer is completely etched by a one-step hydrothermal method to generate a hedgehog-shaped shell structure, and after reaction, deionized water cleaning and magnet collection are performed to obtain the hedgehog-shaped magnetic microsphere. The microsphere is characterized in that the microsphere comprises an inner core and a magnesium silicate shell, and the magnesium silicate shell is of a nano needle-shaped structure, looks like a hedgehog and has a powerful surface function; and the inner core is magnetic ferroferric oxide nano particles, and the microsphere is endowed with rapid magnetic responsiveness, so that controllable movement of the hedgehog-shaped magnetic microsphere can be realized under the action of an external magnetic field. The preparation method of the hedgehog-shaped magnetic microspheres based on the magnetic nano particles has the advantages of low cost, easiness in operation, convenience, reliability and the like.

The invention discloses a Mn-Fe-P-Si-based magnetic refrigeration material with low heat stagnation and a preparation method thereof, and belongs to the technical field of magnetic refrigeration materials. The material comprises the component of (Mn,Fe)<2-x>Nb<x>(P,Si), wherein 0.02<=x<=0.04. The method comprises the following steps: weighing a manganese sheet, iron powder, niobium powder, a phosphorus block and a silicon block according to the molar ratio of each element in the chemical formula; carrying out ball milling under the protection of argon; putting the ball-milled powder into a mold, and pressing into a wafer; and carrying out annealing treatment on the pressed sample under argon, and then rapidly quenching the sample into cold water to prepare the sample. According to the method, a proper amount of Nb is doped into the (Mn, Fe)<2>(P, Si) material, so that the phase change temperature is continuously adjustable near the room temperature, the heat stagnation is greatly reduced, larger magnetic entropy change is kept, and the application of the material in room-temperature magnetic refrigeration is facilitated.

The invention relates to a method for preparing silicon hydroxyl magnetic microspheres. The method comprises the following steps of synthesizing magnetic particles, carrying out hydrophilic layer modification on the magnetic particles, and carrying out functionalization treatment on the modified magnetic particles, wherein the functionalization treatment comprises the following substeps of dispersing the modified magnetic particles in an anhydrous lower alcohol solution, adding a monomer imparting functionalization to the silicon hydroxyl groups of the magnetic particles for reaction. No wateris added in the step of the functionalization treatment and no aqueous reagent other than a pH adjusting agent is used in the step of the functionalization treatment. The extraction effect of nucleicacid, especially RNA, is improved. The invention further relates to the prepared silicon hydroxyl magnetic microspheres and application of the silicon hydroxyl magnetic microspheres in nucleic acid extraction.