404results about "Ferroso-ferric oxides" patented technology

The invention belongs to the technical field of wastewater treatment and energy recovery, and provides a regulation and control method for promoting anaerobic acid production by taking soybean molasses as a substrate through cooperation of ferroferric oxide and bamboo charcoal. Soybean molasses is used as a substrate carbon source, anaerobic activated sludge is inoculated in a medium-temperature SBR reactor, the volume ratio of reactor inflow sewage to sludge is 2: 1, ferroferric oxide and bamboo charcoal composite conductive particles which are subjected to ball milling treatment and have the concentration of 1 g / L are added to promote an anaerobic fermentation system to produce acid, and then anaerobic fermentation is carried out. The mass ratio of ferroferric oxide to bamboo charcoal in the ferroferric oxide and bamboo charcoal composite conductive particles is (1: 2)-(2: 1); monitoring the acid yield, the pH value change and the product type; and the variety and concentration of the acid-producing substance are analyzed, and the interaction of all the components in the reaction process is evaluated. The acid production rate and the total acid production amount in the anaerobic acid production process are obviously improved. And the activity of anaerobic flora is promoted. The variety distribution of acid-producing substances is obviously optimized, and the stability of the acidification process is improved.

The invention belongs to the field of adsorption materials, and discloses a porous lignin fiber adsorption material and a production process thereof, the porous lignin fiber adsorption material comprises the following raw materials by weight: 40-60 parts of lignin fiber, 20-30 parts of bamboo fiber, 5-15 parts of chitosan, 5-10 parts of sodium bicarbonate, 5-10 parts of attapulgite, 5-10 parts of zeolite, and 2-5 parts of magnetic nanoparticles; the invention aims to provide the production process of the porous lignin fiber adsorption material, the problems that the existing lignin fiber adsorption material is poor in pore structure, limited in adsorption performance, difficult to separate and the like are solved through an innovative raw material formula and an optimized production process, efficient adsorption of light components in asphalt is realized, the stability of an asphalt mixture is enhanced, and the service life of the asphalt mixture is prolonged. Meanwhile, heavy metal ions, organic pollutants and the like are efficiently adsorbed and rapidly separated, the production energy consumption is reduced, and the environmental protection property and economical efficiency of the process are improved.

The invention discloses a preparation method of a wear-resistant magnetic composite nano ferroferric oxide material, and belongs to the technical field of nano ferroferric oxide materials.The preparation method comprises the steps that coated modified ferroferric oxide composite powder, silver nitrate and absolute methanol are added into a reaction kettle, stirring and ultrasonic dispersion are conducted, then 2-aminoterephthalic acid is added, stirring and mixing are conducted, and a mixture is obtained; and after the reaction, separating to obtain the wear-resistant magnetic composite nano ferroferric oxide material. The wear-resistant magnetic composite nano ferroferric oxide material prepared by the preparation method disclosed by the invention overcomes the problem that an existing ferrite material is relatively single in electromagnetic loss mechanism in the aspect of nickel-phosphorus plated fabric, and the electromagnetic shielding effectiveness of the fabric is improved; the coated modified ferroferric oxide composite powder has good dispersity, a polydopamine coating layer on the surface of the coated modified ferroferric oxide composite powder improves the anchoring effect on silver MOF particles through a mussel-like adhesion interface, meanwhile, stress is dispersed and crack propagation is reduced through the buffering effect of the polydopamine coating layer, and the mechanical stability of the wear-resistant magnetic composite nano ferroferric oxide material is improved.

The invention belongs to the technical field of lithium battery material recovery, and particularly relates to a method for recovering a waste lithium iron phosphate positive electrode material. The method comprises the following steps: (1) grinding and sieving the positive electrode material of the waste lithium iron phosphate battery, mixing with an alkaline solution, stirring and leaching, and carrying out solid-liquid separation to obtain a lithium-rich solution and leaching residues; (2) introducing a saturated sodium carbonate solution into the obtained lithium-rich solution, carrying out heating reaction, filtering, taking a solid phase, and drying to obtain lithium carbonate; and the obtained leaching residues are dried, and ferroferric oxide is obtained. According to the method, the waste lithium iron phosphate battery positive electrode material is leached through the alkaline liquid phase, it can be guaranteed that lithium and iron in waste lithium iron phosphate are separated through a one-step leaching method, and therefore selective lithium extraction is achieved. The whole technological process is convenient to operate, mild in reaction condition and low in energy consumption, does not need to use any acid or oxidant, avoids generation of a large amount of waste liquid and harmful gas, and is high in selective lithium extraction efficiency.

The application relates to a method for one-step synthesis of strong magnetic hydrophobic Fe3O4 nanoparticles at low temperature and the Fe3O4 nanoparticles and application, and belongs to the technical field of nano material preparation. The method comprises the following steps: adding a ferrous sulfate solution into a mixed solution of sodium hydroxide and sodium nitrate, heating and stirring to react, adding oleic acid in the reaction process, and obtaining black Fe3O4 crystals after the reaction is completed. The saturation magnetization of the obtained strong magnetic hydrophobic Fe3O4 nanoparticles can reach 85.69 emu / g at most, and the water contact angle can reach 148.95 DEG. The one-step synthesis reaction only needs to use oleic acid as a regulator, avoids an extreme high-temperature and high-pressure environment, does not need to use a toxic chemical solvent, the condition is mild, the process is simple, the operation condition is easy to control, and the method has a wide application prospect.

According to the method, sodium carbonate, limestone and coke are used as sintering aids and are uniformly mixed with the high-iron Bayer process red mud, the mixed material is sintered by adopting a one-step low-calcium reduction sintering process, and the sintered clinker is subjected to water leaching and dissolution to obtain a sodium aluminate crude solution and filter residues. And returning the sodium aluminate crude liquid to an aluminum oxide industrial production line to prepare aluminum oxide, and carrying out a hydrolysis alkali recovery process on filter residues to obtain industrial sodium carbonate. The hydrolysis residues are subjected to magnetic separation and recovery to obtain fine iron powder, and the remaining tailings are completely harmless and can be used as raw materials of building materials or used for soil backfilling. The process is characterized in that the one-step low-calcium reduction sintering temperature is 200-300 DEG C lower than the sintering temperature of a sintering method, and the energy consumption is low; na2CaSiO4 is a sintering target product, Ca2SiO4 generally generated by a traditional sintering method is not generated, the situation that Ca2SiO4 is hydrolyzed in the water leaching process to inhibit dissolution of aluminum oxide is avoided, and the recycling rate of aluminum oxide is increased while the using amount of limestone is greatly reduced. The technological process is simple, efficient, energy-saving and free of three-waste emission, and the method is a novel method capable of treating the high-iron red mud in a large-scale and reduction mode.

The invention relates to the technical field of recycling of waste battery materials, and discloses a recycling method of lithium iron phosphate battery waste, which comprises the following steps: carrying out sufficient acid leaching on the lithium iron phosphate battery waste, and carrying out solid-liquid separation to obtain a leachate; adding a sufficient amount of iron ion complexing agent competing with phosphate radicals and a sufficient amount of lithium precipitation inhibitor competing with lithium ions into the leachate, and diluting to obtain a mixed solution; the temperature is controlled to be 20-50 DEG C, alkali liquor is gradually added into the mixed solution, when the pH value of the solution reaches 3.5-4.5, the alkali liquor continues to be added, oxygen is introduced into the solution at the same time, when ferrous iron in the solution is oxidized to 30-40%, oxygen introduction is stopped, the condition is maintained for 8-12 min, after it is detected that a ferroferric oxide product appears in a system, the pH value of the solution is rapidly adjusted to 7.5-8.5, and the ferroferric oxide product is obtained. Fully aging to obtain slurry containing ferroferric oxide; and ferroferric oxide is extracted from the slurry. According to the method, ferroferric oxide with relatively high purity can be recovered and obtained.

The invention belongs to the technical field of SERS (Surface Enhanced Raman Scattering) detection, and relates to a preparation method of an Ag-Fe3O4 composite SERS substrate and application of the Ag-Fe3O4 composite SERS substrate in monitoring trace pollutants in water. Based on a plasma-semiconductor synergistic enhancement mechanism, cubic Fe3O4 nano particles with exposed {100} crystal faces are synthesized through a hydrothermal method, and the cubic Fe3O4 nano particles and Ag nano particles are subjected to ultrasonic-stirring to construct the Schottky heterojunction. The substrate creatively realizes dual-channel enhancement: the local surface plasmon resonance effect of Ag nanoparticles generates electromagnetic enhancement, the narrow band gap of Fe3O4 promotes photo-induced electrons to be transferred to Ag, an interface electric field is formed, and the polarizability of adsorption molecules is remarkably increased. When the probe is applied to detection of trace pollutants in a water body, the probe molecule RB is anchored on the surface of Fe3O4 through carboxyl, and the HOMO energy level of the probe molecule RB and the valence band top of Fe3O4 generate resonance charge transfer, so that the Raman cross section is improved. The detection limit of RB under 0.25 mW laser is increased by several orders of magnitude compared with that of a single Ag substrate.

The invention discloses lithium sulfide and a preparation method thereof. The preparation method comprises the following steps: (1) carrying out ball-milling mixing on iron powder, sodium sulfide and lithium sulfate in a first inert atmosphere to obtain a mixture; (2) calcining the mixture in a second inert atmosphere for the first time to obtain a reaction material; (3) stirring and washing the reaction material with an alcohol solvent in a third inert atmosphere, filtering to obtain filtrate and a filter cake, performing reduced pressure distillation on the filtrate to obtain a lithium sulfide crude product, washing the filter cake with deionized water, and filtering to obtain a solid by-product; and (4) carrying out secondary calcination on the lithium sulfide crude product in a fourth inert atmosphere to obtain lithium sulfide. The preparation method provided by the invention has the advantages of few synthesis steps, simple product purification and environmental protection.

The invention discloses a resource recycling method of waste lithium iron phosphate batteries, which comprises the following steps: mixing lithium iron phosphate black powder and a chlorinating agent, and performing chlorination separation roasting to obtain roasted sand and flue gas; and the roasted product is subjected to leaching treatment, and flue gas is subjected to defluorination and dechlorination treatment through a semi-dry method. According to the recycling method, the chlorinating agent is introduced for chlorination separation roasting, phosphorus in lithium iron phosphate reacts with the chlorinating agent to generate a phosphorus-containing compound phase, high-temperature reduction conversion of iron is achieved through graphene / carbon black in the black powder, and a magnetite phase is formed; a phosphorus-containing compound phase and a magnetite phase generated in the chlorination segregation roasting process are subjected to high-temperature segregation, and lithium exists in the form of a lithium-containing compound. And the roasted sand and the flue gas are treated at the same time, so that various recycled products can be obtained, the emission of the flue gas is reduced, and the high-value recycling purpose is achieved.

The invention discloses terahertz wave-absorbing foam based on magnetically-induced gradient distribution carbon nanotubes and a preparation method, and belongs to the technical field of photoelectric materials and devices. The terahertz wave-absorbing foam comprises a porous framework and a wave-absorbing agent distributed in the porous framework, wherein the porous skeleton is a PDMS matrix with holes, the wave-absorbing agent is MWCNT modified by Fe3O4 nanoparticles, and the mass percentage of the wave-absorbing agent in the wave-absorbing foam is 3-7wt%. The dielectric constant of the wave-absorbing foam is regulated and controlled by controlling the concentration of the MWCNT modified by the Fe3O4 nanoparticles, and the concentration of the MWCNT can be guided to be distributed in a longitudinal gradient manner by using an external magnetic field, so that surface electromagnetic impedance matching is realized, and finally reflection suppression and absorption enhancement of electromagnetic waves are completed; meanwhile, large-area preparation can be realized by using white granulated sugar as a sacrificial template, and the method is suitable for industrial production.

The invention relates to a preparation process of a lithium ion composite battery negative electrode material with low impedance and high rate performance. The preparation method comprises the following steps: pretreatment of artificial graphite, preparation of hollow ferroferric oxide nanospheres (H-Fe3O4), preparation of disordered nitrogen-doped carbon-coated hollow ferroferric oxide nanospheres (H-Fe3O4 (at) NC), preparation of carbon-coated artificial graphite (Ag (at) C), preparation of a porous graphite composite material (PG (at) C (at) SEI for rapid charging, preparation of an artificial SEI high-conductivity porous graphite negative electrode material (PG (at) C (at) SEI), and construction of the composite negative electrode material (rGO (at) PG (at) C (at) SEI (at) H-Fe3O4 (at) NC). According to the preparation method, a high-temperature treatment method, a doping combination method, a carbonization combination method and an etching method are creatively combined, the prepared battery negative electrode material shows good impedance high-rate performance, and the charging and discharging efficiency and the cycling stability of a lithium ion battery can be effectively improved.

The invention discloses a functionalized nano magnetic iron-based material as well as a preparation method and application thereof. The functionalized nano magnetic iron-based material comprises a magnetic Fe3O4 core, a SiO2 isolating layer, a polydopamine electron transfer strengthening layer and a positively charged polymer three-dimensional microspace conducting layer, the magnetic Fe3O4 core, the SiO2 isolating layer, the polydopamine electron transfer strengthening layer and the positively charged polymer three-dimensional microspace conducting layer are sequentially arranged from inside to outside. According to the invention, rapid recovery of materials is realized through design of magnetic components (sedimentation time lt; 5 min) and cyclic utilization (more than or equal to 10 times); the dispersibility of the material and the affinity of microorganisms are improved through surface functionalization design; and the starting period is shortened by more than 50% through an electron transfer process strengthening and directional microorganism enrichment synergistic interaction mechanism.

The invention designs a preparation method of a magnetic molecular imprinting-aptamer sandwich fluorescence sensor for detecting kanamycin. And the magnetic molecular imprinting composite material Fe3O4 (at) UiO-66 (at) MIP with a specific adsorption target object KANA is prepared. When a detection target object KANA exists, the Fe3O4-coated UiO-66-coated MIP can rapidly and specifically capture the KANA in a short time. Then, a DNA single-stranded aptamer marked with FAM is added, after the aptamer and KANA captured on the surface of the Fe3O4 at-UiO-66 at-MIP are subjected to specific recognition and magnetic separation again, an aptamer probe can enter sediment along with the magnetic composite material Fe3O4 at-UiO-66 at-MIP, the fluorescence intensity of supernate is reduced, and quantitative analysis is conducted according to the fluorescence difference value delta F. When the KANA does not exist, the aptamer cannot enter the precipitate, so that the fluorescence signal intensity is not changed. Double recognition is formed through specific binding of an MIP imprinting cavity and the aptamer, matrix interference is reduced by means of fluorescence characteristics and magnetic separation capacity, the method has the advantages of being high in adsorption capacity, specific in recognition, high in sensitivity, wide in detection range, good in selectivity and the like, and rapid and accurate detection of KANA in a complex sample can be achieved.

The invention provides a magnetic bead extraction reagent, a kit and an extraction method. The magnetic bead extraction reagent is characterized by comprising a magnetic bead liquid I and a magnetic bead liquid II, the magnetic bead liquid I contains magnetic beads I; the magnetic bead liquid II contains magnetic beads II and does not contain an alcohol solvent; the magnetic beads I are used for removing impurities from a to-be-extracted biological sample containing nucleic acid, and the magnetic beads II are used for adsorbing the nucleic acid. By adopting the reagent or the kit disclosed by the invention, the bacterial liquid can be directly extracted without centrifugal treatment, and high-quality nucleic acid can be directly extracted after a bacterial liquid operation program is added. The flux is large, and nucleic acid of 32 samples can be extracted at most at a time. By utilizing the reagent, the kit and the matched procedure, the activity of the hydroxyl magnetic beads is ensured, and high-quality plasmids are extracted.

The present invention provides a method of producing hydrochloric acid, comprising reacting high-temperature gaseous chlorine and water vapour in a carbon-free reverse Deacon reaction (RDR) at a temperature of from about 450 to about 750 °Celsius to produce a mixture of gases comprising hydrogen chloride and oxygen. The chlorine is produced by fusing and electrolysing sodium or magnesium chloride in solid phase. The water vapour comes from thermally decomposing a hydroxide of at least one of calcium, magnesium and iron in the absence of oxygen to produce the water vapour without any admixture of oxygen (e.g., from atmospheric air). The mixture of gases produced by the RDR is immediately contacted with liquid water to dissolve the hydrogen chloride therein, thereby producing hydrochloric acid and a stream of tail gases. Heat is extracted from the hydrochloric acid to maintain its temperature substantially constant until the stream of tail gases is no longer in contact therewith. Thus the chlorine and water vapour are both supplied to the RDR at high purity and require little, if any, preheating. Heat extracted from contacting the mixture of gases with liquid water may be used to keep the RDR within its range of operating temperatures. Oxygen can be separated from the stream of tail gases, and the oxygen-depleted stream can be recycled back to the RDR to give a high percentage conversion of chlorine to hydrogen chloride. The RDR may be uncatalysed and kept within its operating temperature range by radio-frequency volumetric heating in at least one of the IEEE Ku-, K- and Ka-bands. The invention also provides a corresponding apparatus (1h) for producing hydrochloric acid, comprising an electrolytic cell (10) for the electrolysis, a gas-tight kiln (20) for the thermal decomposition, a gas-phase reactor (30) for the RDR, and an absorber (40) for dissolving the hydrogen chloride in the liquid water. The apparatus (1h) may further comprise a separator (80) for separating the stream of tail gases into the oxygen-depleted stream and a stream of oxygen, which may be fed to a steelmaking apparatus (90), for example. The liquid water for dissolving the hydrogen chloride can come from condensing water vapour obtained by drying an aqueous solution of sodium or magnesium chloride or of sodium hydroxide. The apparatus (1h) may therefore also comprise a dryer (60) for drying this aqueous solution, and a condenser (70) for condensing the water vapour thus obtained. Sodium chloride or magnesium chloride in solid phase derived from drying the aqueous solution may be recycled back to the electrolytic cell (10). Electricity for the electrolysis can come from a renewable resource. At least some of the heat for the thermal decomposition may come from the liquid metal which is a co-product of the electrolysis. The invention is therefore highly energy efficient and requires little, if any, extra energy, apart from the electricity required for the electrolysis. The invention also uses commonly available ingredients and produces no greenhouse gases.

Herein described is a method for making a composite material, comprising the steps of (a) swelling a blank hydrogel or a blank organogel using an inorganic precursor mixture to form an inorganic precursor-containing solvent-containing gel, wherein the inorganic precursor mixture comprises a solvent and one or more inorganic precursors, and (b) converting the inorganic precursor into ceramic or metal within the solvent-containing gel by introduction of reagents and / or stimuli to obtain a composite material. Optionally, the composite material can be converted into an inorganic material with an additional step (c) comprising thermally treating the composite material. Also described are the resultant composite material and the optional resultant inorganic material.

The invention relates to the field of nano materials and photonic crystal materials, in particular to nano particles, preparation of the nano particles and application of the nano particles in self-assembly of three-dimensional non-close-packed photonic crystals. The nanoparticles can be self-assembled into a three-dimensional non-close-packed photonic crystal in a concentration range of 1 wt%-60 wt%. According to the invention, the problem that the self-assembly of the three-dimensional non-close-packed colloid photonic crystal is difficult to realize at low concentration at present is solved. By adjusting the mass fraction of the particles in a solution, the three-dimensional non-close-packed colloidal photonic crystal with rich colors can be formed through self-assembly, and the three-dimensional non-close-packed colloidal photonic crystal has wide application prospects in the fields of sensing, display and the like.

The invention relates to the technical field of electromagnetic wave absorbing materials, in particular to a composite material and a preparation method and application thereof. The composite material is prepared from magnetic microspheres, modified SiO2 aerogel and Mxene, wherein the magnetic microsphere comprises an inner core and a coating layer, the inner core comprises Fe3O4, the surface of the inner core is at least partially coated with the coating layer, and the coating layer comprises SiO2; a modified group of the modified SiO2 aerogel comprises at least one of amino, hydroxyl and carboxyl; the magnetic microspheres are positioned on the two-dimensional surface of the MXene. According to the composite material, through the synergistic effect of the magnetic microspheres, the modified SiO2 aerogel and the MXene, impedance matching between the composite material aerogel and air is remarkably enhanced, and the electromagnetic wave absorption performance of the composite material is promoted.

This invention discloses a magnetic nano-silica, its preparation method, and its application in the enrichment of low-abundance proteins. The proposed method for preparing magnetic silica, while preserving the surface properties of silica and maintaining its protein adsorption capacity, also imparts magnetism; providing a simpler, faster, and more efficient technique for large-scale sample processing. The low-abundance protein enrichment based on magnetic nano-silica proposed in this invention can be applied to almost all sample types, effectively solving the interference caused by high-abundance proteins on the identification of low-abundance proteins during mass spectrometry detection, and increasing the number of identified proteins by 100%-700%.

The invention discloses a two-dimensional heterogeneous self-assembled film and a preparation method thereof. The preparation method comprises the following steps: successfully synthesizing Fe3O4-COOH nanoparticles which are uniform in morphology and stable in size and have carboxyl modified surfaces by adopting an improved solvothermal method; then, the surface of the Fe3O4-COOH is modified with a layer of positively charged polymer BPEI through the electrostatic adsorption effect, and Fe3O4 (at) BPEI is formed; the preparation method comprises the following steps: preparing Fe3O4 (at) BPEI (at) Au, further uniformly adsorbing (12nm) gold nanoparticles on the surface of the Fe3O4 (at) BPEI (at) Au through electrostatic adsorption, finally forming a stable gold shell structure, constructing Fe3O4 (at) BPEI (at) Au with a magnetic core gold shell structure, modifying sulfydryl polystyrene (SH-PS) on the surface of the Fe3O4 (at) BPEI (at) Au, successfully preparing a two-dimensional heterogeneous self-assembled film by taking the Fe3O4 (at) BPEI (at) Au as a construction unit, and constructing the two-dimensional heterogeneous self-assembled film by taking the Fe3O4 (at) BPEI (at) Au as the construction unit. The two-dimensional heterogeneous self-assembled thin film shows good SERS enhancement performance and uniformity, and shows SERS signal sensitization capacity under the action of an external magnetic field.

This invention discloses a magnetic nanomolecular sieve, its preparation method, and its application in the enrichment of low-abundance proteins. The preparation method of the magnetic nanomolecular sieve proposed in this invention is simple to operate, employing a one-pot method. It simultaneously imparts magnetism while maintaining the surface properties of the sieve, i.e., its protein adsorption capacity, thus preserving its magnetic properties. This provides a simpler, faster, and more efficient technical method for large-scale sample processing. The low-abundance protein enrichment based on magnetic molecular sieves proposed in this invention can be applied to almost all sample types, effectively solving the interference caused by high-abundance proteins on the identification of low-abundance proteins during mass spectrometry detection, and increasing the number of protein identifications by 100%-700%.

The application belongs to the technical field of material application, and particularly relates to a graphitized carbon material and a preparation method and application thereof, the preparation method of the graphitized carbon material is as follows: (1) D-(+)-xylose powder and transition metal salt powder are weighed and uniformly ground; (2) after sieving, calcination is carried out under an inert gas atmosphere; (3) after grinding and sieving of the calcined product, washing is carried out with 1.0 mol / L dilute hydrochloric acid solution, then washing is carried out with distilled water and drying is carried out, to obtain the graphitized carbon material, the graphitized carbon material has high adsorption efficiency on aflatoxin B1 (AFB1) in vegetable oil, and in combination with magnetic solid phase extraction (MSPE) and high performance liquid chromatography-fluorescence detection (HPLC-FLD) technology, the detection limit is as low as 2.0 pg·g ‑1 The graphitized carbon material has excellent regeneration performance, and the material consumption and cost in the detection process are significantly reduced.

The invention belongs to the technical field of preparation of nano functional materials, and particularly discloses magnetic nano ferroferric oxide regulated and controlled by polyaspartic acid and a preparation method and application thereof.The preparation method comprises the following steps that 1, a dispersing agent polyaspartic acid or a salt water solution of the polyaspartic acid is added into a Fe < 2 + > / Fe < 3 + > mixed solution, and the mixture is stirred to be uniform to form a precursor dispersion solution; (2) heating the precursor dispersion liquid, dropwise adding an alkali source to adjust the pH value of a reaction system to 8-12, and carrying out a nucleation reaction under ultrasonic treatment; and (3) after the reaction is finished, separating the magnetic particles through an external magnetic field, alternately washing with deionized water and ethanol for 2-5 times, and carrying out vacuum drying to obtain the magnetic nano ferroferric oxide particles. The prepared magnetic nano ferroferric oxide has the particle size of 30-80nm, the saturation magnetization of more than or equal to 36emu / g, stable dispersion and the cell survival rate of more than or equal to 80%. The method solves the problems of particle aggregation, weak magnetism and complex process in the traditional method, can be used for wastewater treatment, and is economical and efficient in process and suitable for large-scale production.

A bi-phased approach between good solvents (or non-polar) and bad solvents (polar) can be used to assemble nanorods into highly ordered monolayers or multilayers of ordered nanorod arrays. These ordered nanorod arrays can display unique optical properties. For example, ordered arrays of CdSe / CdS core / shell nanorods were assembled that display polarized photoluminescence.

The invention discloses a ferroferric oxide, gold, internal label and gold core-shell nanoparticle and a preparation method thereof. Ferroferric oxide is used as a main body, nano-particles which take 16-20 nm gold nano-particles as cores, take sulfydryl molecules with benzene rings as internal standards and have the gold shell thickness of 35-40 nm are adsorbed on the surface of the ferroferric oxide, the overall particle size of the ferroferric oxide nano-particles is 200-460 nm, and the particle size of ferroferric oxide balls is 160-400 nm; the method comprises the following steps: uniformly dissolving ferric chloride, sodium acetate and polyethylene glycol in ethylene glycol according to a mass ratio of (1-2.7): (0.15-0.72): (0.5-2.3), heating to 200 DEG C, keeping the temperature for 8-72 hours, and naturally cooling to room temperature; and putting the product into a drying box, and drying at 60 DEG C. The method comprises the following steps: firstly, preparing Fe3O4 nano-particles, then carrying out surface modification on the Fe3O4 nano-particles, adsorbing 16nm gold seeds to the surfaces of the Fe3O4 nano-particles, adding internal standard molecules, and finally adding ascorbic acid and chloroauric acid to realize gold shell growth on the surfaces of the 16nm gold seeds. The material has the advantages of magnetic aggregation, easiness in separation and the like, and can be applied to the fields of pesticide residue detection, catalytic degradation, environment detection and analysis and the like based on an SERS (Surface Enhanced Raman Scattering) technology.

The application provides a method for preparing a magnetic heterostructure material of magnetite-graphene and application of the magnetic heterostructure material in a directional heat-conducting composite material, and belongs to the technical field of composite materials. The method comprises the following steps: (1) slowly adding a sodium hydroxide solution into a ferric chloride solution under water bath condition to prepare a ferric hydroxide gel, and sequentially performing drying and aging, centrifugation, cleaning and freeze drying on the gel to obtain a ferrous oxide nanocrystal; (2) adding the ferrous oxide nanocrystal, graphene and dopamine hydrochloride into a Tris buffer solution and fully stirring, and performing multiple centrifugation, cleaning and freeze drying to obtain ferrous oxide-dopamine-graphene; and (3) performing calcination reduction on the ferrous oxide-dopamine-graphene to obtain the magnetic heterostructure material of magnetite-graphene. The magnetic heterostructure material prepared by the method can be applied to the preparation of the directional heat-conducting composite material as a heat-conducting filler, and has the advantages of high operability, low cost and the like.

The invention relates to a method for preparing superfine magnetic iron oxide nanoparticles by using liquid nitrogen as a reaction medium, which comprises the following steps: S1, dropping a mixed aqueous solution containing Fe < 3 + > and Fe < 2 + > as a precursor solution and ammonia water into the liquid nitrogen at the same time; s2, stirring while adding ammonia water, and when the mixed solution becomes black, adding oleic acid for particle coating to obtain nanoparticles; and S3, sequentially washing the nano-particles with deionized water and acetone, collecting, filling liquid nitrogen into the obtained nano-particles, and freeze-drying to obtain the superfine magnetic iron oxide nano-particles. The method is easy to operate, the agglomeration phenomenon is effectively prevented under the low-temperature condition of liquid nitrogen, and the prepared nanoparticles have better dispersity and magnetism; due to the use of liquid nitrogen in the reaction process and a subsequent freeze-drying method, the formation of superfine nano-particle powder with uniform size is effectively realized, and the obtained nano-particles have superparamagnetism; the method is environment-friendly and low in cost.

The invention discloses a magnetic nanoparticle-carbon nanotube in-situ composite material as well as a preparation method and application thereof. The composite material comprises a carbon nano tube and magnetic nano particles, the carbon nanotubes are combined with the magnetic metal particles, and the magnetic nanoparticles are distributed among the carbon nanotubes and are distributed near the magnetic metal particles in a concentrated manner. The aerogel formed by floating vapor deposition is in contact with the dispersion liquid with the magnetic nanoparticles, so that the magnetic nanoparticles are guided among the carbon nanotubes, electromagnetic shielding is realized, and in the process, a catalytic source containing magnetic metal elements is adopted, so that magnetic metal particles are constructed in the structure of the carbon nanotubes, and the electromagnetic shielding effect is improved. The metal particles are naturally dispersed and distributed in the carbon nano tube network, so that the magnetic nano particles can be guided to aggregate towards the dispersed metal particles respectively, and uneven distribution and mechanical weakness caused by aggregation of a large number of magnetic nano particles in the space are avoided.

The invention discloses a material reactor, a material reaction system, a method for decomposing a self-oxidation reduction precursor and application. The material reactor comprises a dividing piece and a reaction cylinder, adjusting the rotation of the reaction cylinder; the reaction cylinder is provided with a reaction cavity along the length direction; the dividing piece is placed in the reaction cavity; the dividing piece is provided with at least three dividing plates; one ends of the plurality of sub-plates are connected and are distributed in a surrounding manner by taking the connected position as the center; the other ends of the partial split plates are in contact with the inner wall of the reaction cavity; the material reaction system comprises a rack, a heating device, a feeding device, a discharging device and a material reaction system, according to the scheme, multiple synergistic effects of preventing adhesion, improving heat transfer and accelerating gas-solid reaction can be realized, and the problem of waste caused by the fact that gas decomposed by raw materials does not participate in synthesis and is directly discharged in a production process is solved.