CN1285950A - A kind of magnetic fluid, method and equipment for producing magnetic fluid - Google Patents
A kind of magnetic fluid, method and equipment for producing magnetic fluid Download PDFInfo
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- CN1285950A CN1285950A CN98813070A CN98813070A CN1285950A CN 1285950 A CN1285950 A CN 1285950A CN 98813070 A CN98813070 A CN 98813070A CN 98813070 A CN98813070 A CN 98813070A CN 1285950 A CN1285950 A CN 1285950A
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- magnetic fluid
- magnetic
- carrier liquid
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03C—MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03C1/00—Magnetic separation
- B03C1/32—Magnetic separation acting on the medium containing the substance being separated, e.g. magneto-gravimetric-, magnetohydrostatic-, or magnetohydrodynamic separation
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/44—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of magnetic liquids, e.g. ferrofluids
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y25/00—Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance
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Abstract
本发明涉及一种新的磁流体和生产该磁流体的方法和设备。本发明的目的是提供一种基于极性的载体液体并且具有高的饱和磁化强度即高的纳米颗粒浓度和低的粘度的磁流体,并且提供生产这种磁流体的方法和设备。所述目的是借助于饱和磁化强度至少为30mT、在40EC时的粘度小于100mPaAs的磁流体,和基本上含有外吸收层的非溶解组的载体液体,并且借助于用于生产磁流体的方法和设备来实现的。
The present invention relates to a novel magnetic fluid and a method and apparatus for producing the magnetic fluid. The present invention aims to provide a magnetic fluid based on a polar carrier liquid and having a high saturation magnetization, i.e., a high nanoparticle concentration, and a low viscosity, as well as a method and apparatus for producing the magnetic fluid. This objective is achieved by using a magnetic fluid having a saturation magnetization of at least 30 mT and a viscosity of less than 100 mPaAs at 40°C, and a carrier liquid substantially containing an outer absorbing layer of a non-dissolving group, and by using a method and apparatus for producing the magnetic fluid.
Description
The present invention relates to a kind of new magnetic fluid, and relate to according to claim 1,5,18 before chat the method and apparatus of part producing magnetic fluid.
Magnetic fluid is the stabilising dispersions with superparamagnetism.The solid particle that comprises as decentralized photo in a kind of like this dispersoid will deposit, but this deposition neither gravity produce neither the action of a magnetic field the result.
Magnetic fluid is made up of 3 kinds of components basically.The magnetic component of disperseing comprises that size is the iron material of 3-50 nanometer or the solid particle of ferromagnetic material.Stable with the decentralized photo that form of nanoparticles exists by surfactant.Nano particle is dispersed in uniformly and stably and a kind ofly will be called in the dispersant of carrier liquid at this.Surfactant molecule is noncrystalline molecule, these two kinds of character of its possess hydrophilic property and lipophile.The hydrophilic radical of surfactant sees at particle surface it is changeless from chemical terms, thereby forms the unimolecule absorbed layer.For example, hydroxy-acid group, sulfonate groups, sulfate group, phosphate group or phosphonate groups or amino group all be suitable for use as hydrophilic, at the molecule that chemically can adsorb.Polarity all be suitable for doing carrier liquid with nonpolar solvent.
In order to stablize the nano particle in the polar support liquid (as water), mainly be to form two absorbed layer-internal layers and a skin, can be anionic, cationic or non-ionic surfactant at this outer field noncrystalline molecule; The noncrystalline molecule of internal layer is made of anionic surfactant, as aliphatic acid.Specifically, under the situation of the magnetic fluid of the carrier liquid with water, the second outer absorbed layer is that stable nanoparticles institute is indispensable.
When interior absorbed layer chemically when the hydrophilic radical of surfactant is attached on the particle surface, interacting by more weak physics is adsorbed onto skin on the hydrophilic segment of molecule in the internal layer.In order to form skin, must there be excessive surfactant at aqueous phase.The common practice is that the superficies activating agent is wanted unusual height in the concentration of water, so that produce big bulk viscosity and big accumulation during concentrating water, thereby has limited the magnetic saturation value roughly.Saturation magnetization is the tolerance of magnetic granule density in the magnetic fluid.
Water base magnetic fluid is well-known.According to DE19516323A1, the saturation magnetization that they provide is up to 25mT, and comprises maghemite (γ-Fe as the nano particle of magnetic component
2O
3), magnetic iron ore (Fe
3O
4) or the oxide that mixes, as Conjugate ferrite or manganese-zinc ferrite.Some water base magnetic fluids also exist the shortcoming that has the surfactant of suitable high concentration at aqueous phase like this.The result is them or quite high viscosity is arranged.And, the surfactant overslaugh of high-load magnetically saturated substantially realization.At last, the surfactant of high-load is harmful to aspect ecological, and when produce a considerable number of the time, also be disadvantageous at economic aspect.
In addition, well-known, in the ordinary course of things, in order to reduce surfactant concentrations in the decentralized medium, according to No. the 3917538th, United States Patent (USP), it generally is to handle magnetic fluid in the organic matrix by precipitation again.Particle precipitates as deposit, and decant comprises the dispersant of surfactant, with a kind of surface activity freely its agent is replaced.After heating, dispersion solid particle again is to form magnetic fluid.This method relates to following collateral condition: suitable precipitation is about to form and surfactant can not be removed from solid particle by precipitation.Therefore, it is a kind of thick relatively process of power consumption.Come stable magnetic fluid for wherein particle by interior and outer absorbed layer, can not make in this way.In this case, generally can only remove the skin that only adsorbs from the particle stablizing the polarity decentralized medium with physics mode.
Outer absorbed layer after the complete physical absorption is removed the method for too much surfactant and is not still known at present.
According to DE4130268A1, it is granule modified to use the carboxyl-functional fluidized polymer to make, and at this, dispersant comprises the nonionic wetting agent of carboxyl-functional fluidized polymer and high concentration.In order to produce, under the situation that has the carboxyl-functional fluidized polymer, precipitate magnetite ore particles, then, form deposit by modified particles, this modified particles is dispersed in the dispersant with said components again, and the saturation magnetization of the magnetic fluid that has formed is less than 10mT.In addition, its conductivity is extremely low, is 900 Ω
-1Cm
-1, therefore, when adding electrolyte, the flocculation that produce particle.
US4208294 has described by two absorbed layer stabilized aqueous magnetic fluids, and this absorbed layer comprises laurate and laruate.Similarly, this magnetic fluid also comprises too much laruate.Aqueous dispersion medium must be with some alkalescence slightly.The saturation magnetization that can obtain is about 25mT.A kind of effect of negativity be when the pH value when neutral oxytropism scope moves, particle will precipitate.
DE4327826A1 has described water base magnetic fluid, and magnetic-particle wherein is stable by aliphatic acid in a kind of, and skin is made of fatty alcohol ethoxylate.Because working condition, dispersant will comprise excessive ethoxylated fatty acid, thereby causes magnetic fluid to have quite high viscosity, and the maximum of the saturation magnetization that can obtain only is 25mT.
Therefore, a basic purpose of the present invention provides a kind of magnetic fluid, and this magnetic fluid has high saturation magnetization, promptly high concentrations of nanoparticles and low viscosity, and the present invention also provides a kind of method and apparatus of producing this magnetic fluid.
Said purpose realizes by claim 1,5,15 characteristic.
Have the saturation magnetization of having no precedent so far between 30-100mT according to the magnetic fluid with aqueous carrier liquid of the present invention, and it is lower than 100mPaAs in the viscosity of 40EC.Because nano-particle content height, cause saturation magnetization height according to magnetic fluid of the present invention, add quite low viscosity, so these magnetic fluids are particularly suitable for magnetohydrostatics as medical science pump, sensor process and the material actuating liquid in separating.
The fact that carrier liquid does not contain surfactant has produced benefit ecological aspect and economic aspect.
Use method and apparatus of the present invention to produce to have the magnetic fluid of the present invention of high saturation and magnetic intensity.Surprisingly, known magnetic fluid with quite low saturation magnetization and high surfactant concentration itself is exposed in the external magnetic field, in conjunction with some measures of taking to reduce surfactant concentration in the carrier liquid, just can remove surfactant again.For example, can remove surfactant in the following manner: itself known is passed through an interior absorbed layer and an outer absorbed layer stabilized aqueous magnetic fluid is heated to about 30-95EC, can cause the reduction of the solubility of surfactant in carrier liquid.Magnetic fluid with heating has exposed an external magnetic field then, thereby produces a strong non-uniform magnetic-field-magnetic field gradient in the water-based magnetic fluid.For example, this can be realized by following mode: make a permanent magnet with rare earth element, its surperficial magnetic saturation value allows described permanent magnet play a role up to 0.5T, so that the magnetic fluid of heating is fixed on the wall of a container.After approximately 15-120 minute magnetic field exposure cycles, just can remove those surfactants from magnetic nanoparticle, the surfactant that is removed mainly is to constitute the second outer absorbed layer and be dissolved in those surfactants in the aqueous carrier liquid with high concentration, in this process, also carried away part aqueous carrier liquid secretly, and forced these surfactants to arrive the surface and here from flowing away.Remaining is exactly the magnetic fluid that concentrates.Repeat this process, just might progressively improve the concentration of nano particle, thereby can reach the saturation magnetization of 70mT.Because from carrier liquid, removed a large amount of surfactants, thus can reach obviously low concentrated magnetic fluid viscosity, its at the range of viscosities of 27EC between 5-30mPaAs.
Low like this magnetic fluid viscosity is can be by removing the prerequisite that aqueous carrier liquid further concentrates, for example by evaporating in a rotary evaporator.Realize in this way: at 27EC and in viscosity is 80mT for magnetic saturation value under the situation of 70mPaAs only.Further extract water again, the magnetic saturation value can be up to 100mT.Certainly, viscosity has increased again significantly under this too high magnetic saturation value.This method can be used for carrier liquid polarity and nonpolar.
This concentration process also has an advantage: can reclaim surfactant that separated from nano particle, that come from carrier liquid according to method of the present invention, that dissolved by evaporation, and can use these surfactants once more in this way in the production process of water-based magnetic liquid.
According to the present invention, have following in order to reduce other measure of the solubility of surfactant in carrier liquid:
-interpolation can change the reagent of change pH values;
-change surfactant concentrations by extracting carrier liquid;
-add the solvent and/or the solid that can reduce solubility, as salt and water-soluble polymer;
-interpolation can form the material of aggregation with surfactant molecule.
Describe equipment of the present invention with reference to the accompanying drawings in detail.
Fig. 1 represents the equipment of quasi-continuous exclusion process;
Fig. 2 represents the interrupted equipment of exclusion process in batches.
According to Fig. 1, a container 1 has held the magnetic fluid 10 that will concentrate. Below container 1, establish Put a heating element heater 5. One adds stockline 8 and extends to release surface 2 from the bottom of container 1. Borrow Helping one ends valve 9 and can open and close and add stockline 8. Above release surface 2, be provided with two Strong magnet 3 and 4, they are in close proximity to each other. Separation can be optimized in inclination angle by release surface 2 Effect. Below release surface 2, be provided with a lifting magnet 7 and a surfactant dish 6. By connecting heating element heater 5, the temperature of magnetic fluid 10 can be brought up to about 60EC, can show whereby Reduce the solubility of surperficial popular agent in the carrier liquid of magnetic fluid 10 outstandingly. Opening only valve 9 The time, magnetic fluid 10 will flow to through adding stockline 8 downside of release surface 2. Owing to exist by magnet 3 The magnetic field gradient that produces forms the bulge shape accumulation of a magnetic fluid 10 at release surface 2. Greatly After the about 10 minutes exposure cycles, comprise first carrier fluid of the surfactant of accumulation Body leaves and falls in the surfactant dish 6. When disconnecting magnet 3 and connecting magnet 4 simultaneously, magnetic Fluid 10 will be sucked on the release surface of magnet 4 bottoms, can remove additional surface here Activating agent. After disconnecting magnet 4, in lifting magnet 7, collect residue, i.e. magnetic through highly concentrating Fluid 10.
Fig. 2 is illustrated in the stages of process and removes a kind of of surfactant in batches from carrier liquid Equipment.
According to Fig. 2 a, use heating element heater 5 to add hydrothermomagnetic 10 in the first step. According to Fig. 2 b, connecing Behind the logical magnet 3, magnetic fluid, the nano particle that namely wherein exists is in release surface 2 accumulation. According to figure 2c finishes the concentration process on release surface 2, and collects the particle that has concentrated in the bottom. Subsequently, The magnetic fluid that can collect in the bottom is added in the container 1 separation process that repeats to add again.
Below with reference to embodiment method of the present invention is described in further detail.
Embodiment 1
Concentrate the magnetic fluid that contains magnetite ore particles of a kind of water base 15mT according to the following stated method, this magnetic fluid has a laurate layer and second nonionic layer with ethoxy alcohol of ethoxy group that adds on the particle:
In a fiery container of anti-height, 100 milliliters of magnetic fluids are heated to 80EC.A rare earth element permanent magnet that with the saturation magnetization on surface is 0.3T subsequently is fixed on the outer wall of container, thereby makes magnetic fluid remain on the opposite side of magnet.After a few minutes, the viscosity solution of non-magnetic begins to separate from magnetic fluid.The magnetic fluid increasing along with the past concentration of time forms typical mountain peak shape after certain time, more and more closely be fixed on the magnet.Can promote separation process by following method: keep magnetic fluid to be among the motion by moving magnet or by the mechanical agitation magnetic fluid, perhaps magnetic fluid is reheated 80-90EC.The saturation magnetization of final products is 50mT, is 5mPaAs in the dynamic viscosity of 27EC.
By the evaporation water, the saturation magnetization value might be brought up to 80mT, the viscosity of the magnetic fluid of this moment only is increased to 70mPaAs.Further evaporation will obtain the magnetic dispersion of a high viscosity, and the saturation magnetization value of this magnetic dispersion is 100mT.
Handle the magnetic fluid that contains magnetite ore particles of a kind of water base 10mT according to the following stated method, this magnetic fluid has oleic acid layer adding its top to and the second nonionic layer of an oleic acid Isosorbide Dinitrate:
In a container, magnetic fluid is heated to 90EC.The rare earth element permanent magnet that a golden filling of usefulness is coated is directly put into magnetic fluid subsequently.The magnetic fluid that adheres on the magnet is transferred in the new container, separates at this.The saturation magnetization value of final products is 50mT, is 10mPaAs in the viscosity of 27EC.
In the semi-continuous process of the following stated, handle the magnetic fluid that contains the Conjugate ferrite particle of a kind of water base 20mT, but other described magnetic fluid also includes the surfactant layer of mentioning in the foregoing description:
At first magnetic fluid is heated to 80EC.Powerful electromagents are installed on a glass plate or on the plastic plate, and are made them have slightly a bit.Add the downside that stockline is delivered to warmed-up magnetic fluid glass plate or plastic plate by a tubulose subsequently.Separation process begins, and the surfactant solution that comes from magnetic fluid drips earthward.Provide magnetic fluid continuously to magnet, till the amount of the magnetic fluid accumulation that concentrates equals will be from amount that magnet flows out the time.
Now, the magnetic field of electromagnet reduces gradually, thereby the magnetic fluid that allows to concentrate flows into a gathering-device dividually.By connecting magnet and providing magnetic fluid can restart this process.The saturation magnetization value of final products is 60mT, is 20mPaAs in the viscosity of 27EC.
By the hydrochloric acid that adds dilution make water base 20mT the magnetic fluid that contains magnetite ore particles its be in alkaline medium with the stable magnetic fluid of two-layer laurate, the magnetic fluid here becomes to have slightly and stablizes.Magnetic fluid is heated to 80EC, carries out 2 described processing subsequently as embodiment.If use the Ammonia that concentrates, the pH value of final products is greater than 8, and at this moment, particle has taken place to disperse again.The saturation magnetization value of final products is 60mT, and viscosity is 5mPaAs.
Initial magnetic fluid is the water-based magnetic iron ore magnetic fluid that is adjusted to alkalescence, and particle wherein is stable by the outer absorbed layer of absorbed layer in lauric and laurate ammonium salt according to US4208294, and the saturation magnetization of this magnetic fluid is 15mT.
Under the condition of not destroying magnetic fluid, the dilute solution by slow adding ethanol and hydrochloric acid makes the surfactant that dissolves in the carrier liquid of water-based form surfactant aggregates.After this, the decentralized medium of part and separating of the surfactant that wherein comprises in magnetic field gradient, have been realized.Subsequently, readjust the alkaline pH value by in the magnetic fluid that concentrates, adding ammonium hydroxide.The magnetic fluid that concentrates at room temperature and the saturation magnetization under 100mPaAs viscosity be 80mT.
Embodiment 6
As initial magnetic fluid, described magnetic fluid is stable by means of an individual layer of oleic acid based on the magnetic iron ore magnetic fluid of oil in use, and its saturation magnetization is 30mT.By ratio adding ethanol the oleic acid that comprises oil is condensed with 1: 2.When being exposed to the external magnetic field, this saturation magnetization is increased to 100mT, is 20mPaAs in the viscosity of 27EC.
Label list
1, container
2, release surface
3, magnet
4, magnet
5, heating element
6, surfactant dish
7, lifting magnet
8, add stockline
9, end valve
10, magnetic fluid
Claims (21)
1, a kind of magnetic fluid, it comprises a kind of carrier liquid of polarity and by two magnetic nanoparticles that the unimolecule absorbed layer is stable, it is characterized in that: the saturation magnetization by described magnetic fluid is at least 30mT, and the viscosity when 40EC is 100mPaAs, and described carrier liquid does not comprise the solvent components of outer absorbed layer basically.
2, according to the magnetic fluid of claim 1, it is characterized in that: the carrier liquid of described polarity is water and/or liquid that can be miscible with water, for example ethylene glycol or formamide.
3, according to the magnetic fluid of claim 1 or 2, it is characterized in that; Described magnetic nanoparticle is of a size of 3-5nm.
4, according to any one magnetic fluid among the claim 1-3, it is characterized in that: described saturation magnetization is 30-100mT.
5, a kind of method that is used to produce highly enriched magnetic fluid, this magnetic fluid is based on nonpolar and carrier liquid and magnetic nanoparticle polarity, this nano particle is stable by one or both absorbed layers, this carrier liquid comprises surfactant, it is characterized in that: after providing or adding the reagent that can reduce the surfactant dissolves degree, to comprise surfactant polarity be exposed to an external magnetic field with nonpolar carrier liquid, and after the irradiation of said external magnetic field, from the surfactant of nano particle precipitation separation carrier liquid.
6, according to the method for claim 5, it is characterized in that: the minimum value of the intensity of the external magnetic field that is used for shining is 0.2T.
7, according to the method for claim 5 or 6, it is characterized in that; Magnetic field pre-irradiation externally, the magnetic fluid that will concentrate is heated to 30EC at least.
8, according to any one method among the claim 5-7, it is characterized in that: magnetic fluid is heated to 30-95EC, particularly 60-80EC.
9, according to any one method among the claim 5-8, it is characterized in that: add the reagent that changes change pH values, as acid, alkali or salt.
10, according to any one method among the claim 5-8, it is characterized in that: interpolation can reduce the solvent and/or the solid of solubility, as other surfactant, salt and/or water-soluble polymer.
11, according to any one method among the claim 5-8, it is characterized in that: add the reagent that only absorbs carrier liquid.
12, according to any one method among the claim 5-11, it is characterized in that: described magnetic fluid was exposed to the external magnetic field at least 5 minutes.
13, according to any one method among the claim 5-12, it is characterized in that: described magnetic fluid is exposed to the external magnetic field of 0.1-1.5T.
14, according to any one method among the claim 5-13, it is characterized in that: described magnetic fluid is exposed to a plurality of external magnetic fields that intensity increases gradually.
15, according to any one method among the claim 5-14, it is characterized in that: the described liquid of isolated vectors is reused.
16, according to any one method among the claim 5-15, it is characterized in that: use the magnetic fluid of the carrier liquid with polarity, for example water and/or the liquid that mixes with water soluble are as ethylene glycol or formamide.
17, according to any one method among the claim 5-15, it is characterized in that: use magnetic fluid with non-polar support liquid.
18, a kind of equipment that is used to produce highly enriched magnetic fluid, this magnetic fluid are based on the carrier liquid and the magnetic nanoparticle of polarity, and this nano particle has two unimolecule absorbed layers, and described equipment comprises:
-one container (1) that is used for magnetic fluid;
-release surface (2) and
-magnetic field gradient generating means (3),
Described magnetic field gradient generating means (3) is set at release surface (2) and locates.
19, according to the equipment of claim 18, it is characterized in that: container (1) has a heating element (9) that is used for magnetic fluid.
20, according to the equipment of claim 18 or 19, it is characterized in that: magnetic field gradient generating means (3) be oriented in gravity direction.
21, according to equipment any one among the claim 18-20, it is characterized in that: the magnetic field gradient generating means (3) that a plurality of intensity are increased gradually is in line.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19758350A DE19758350C1 (en) | 1997-12-22 | 1997-12-22 | Magnetic fluid comprising magnetic nano-particles dispersed in a polar carrier fluid |
| DE19758350.4 | 1997-12-22 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1285950A true CN1285950A (en) | 2001-02-28 |
Family
ID=7853655
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN98813070A Pending CN1285950A (en) | 1997-12-22 | 1998-12-17 | A kind of magnetic fluid, method and equipment for producing magnetic fluid |
Country Status (9)
| Country | Link |
|---|---|
| EP (1) | EP1051715A1 (en) |
| JP (1) | JP2001527283A (en) |
| KR (1) | KR20010033478A (en) |
| CN (1) | CN1285950A (en) |
| AU (1) | AU2162299A (en) |
| CA (1) | CA2315704A1 (en) |
| DE (1) | DE19758350C1 (en) |
| RU (1) | RU2203516C2 (en) |
| WO (1) | WO1999033072A1 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102441488A (en) * | 2011-09-06 | 2012-05-09 | 北京交通大学 | Slide-type gas-liquid interface jigging magnetic separation controllable device |
| CN107195419A (en) * | 2017-08-02 | 2017-09-22 | 新疆大学 | Ethylene glycol magnetic fluid and preparation method thereof |
| CN108037700A (en) * | 2017-12-13 | 2018-05-15 | 杭州电子科技大学 | A kind of magnetic current body controlling means |
| CN110495080A (en) * | 2017-04-14 | 2019-11-22 | 开利公司 | Increased motor winding inductance |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102006041495A1 (en) * | 2006-08-29 | 2008-03-20 | Friedrich-Schiller-Universität Jena | Substance mixture, useful for locally limited of magnetic nanoparticle within or directly at the edge of tumor affected physical tissue, where the magnetic particle is mixed with a fluid thixotropic carrier substance |
| RU2337422C1 (en) * | 2006-12-11 | 2008-10-27 | Открытое акционерное общество "Научно-исследовательский и проектный институт по переработке газа" ОАО "НИПИгазпереработка" | Method of magnet liquid stabilisation |
| UA87177C2 (en) * | 2007-07-04 | 2009-06-25 | Государственное Предприятие "Международный Центр Электронно-Лучевых Технологий Института Электросварки Им. Е.О.Патона Национальной Академии Наук Украины" | method of producing nanoparticles for magnetic fluids by electron-beam evaporation and condensation in vacuum, method of producing magnetic liquid and magnetic liquid produced by said method |
| RU2391729C1 (en) * | 2008-12-02 | 2010-06-10 | Государственное образовательное учреждение высшего профессионального образования "Ярославский государственный технический университет" | Method of preparing magnetic liquid |
| US9409148B2 (en) | 2013-08-08 | 2016-08-09 | Uchicago Argonne, Llc | Compositions and methods for direct capture of organic materials from process streams |
| JP7059358B2 (en) * | 2018-03-30 | 2022-04-25 | 富士フイルム株式会社 | Separation device and separation method |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3917538A (en) * | 1973-01-17 | 1975-11-04 | Ferrofluidics Corp | Ferrofluid compositions and process of making same |
| US4208294A (en) * | 1979-02-12 | 1980-06-17 | The United States Of America, As Represented By The Secretary Of The Interior | Dilution stable water based magnetic fluids |
| JPH04107802A (en) * | 1990-08-28 | 1992-04-09 | Nippon Seiko Kk | Production of magnetic fluid |
| US5240626A (en) * | 1990-09-21 | 1993-08-31 | Minnesota Mining And Manufacturing Company | Aqueous ferrofluid |
| RU2057380C1 (en) * | 1992-09-14 | 1996-03-27 | Редкинский опытный завод | Magnetic fluid concentrate and its production process |
| RU2056067C1 (en) * | 1992-12-31 | 1996-03-10 | Владимир Николаевич Наумов | Water base magnetic fluid |
| DE4327826C2 (en) * | 1993-08-16 | 1995-06-08 | Ikosta Gmbh Inst Fuer Korrosio | Magnetic liquid |
| DE19514515C2 (en) * | 1995-04-12 | 1997-03-20 | Dirk Dipl Chem Guenther | Magnetizable dispersions |
| DE19516323C2 (en) * | 1995-04-27 | 1997-02-27 | Dirk Dipl Chem Guenther | Process for the preparation of magnetizable dispersions and their use |
| US5667716A (en) * | 1996-07-01 | 1997-09-16 | Xerox Corporation | High magnetization aqueous ferrofluids and processes for preparation and use thereof |
-
1997
- 1997-12-22 DE DE19758350A patent/DE19758350C1/en not_active Expired - Fee Related
-
1998
- 1998-12-17 WO PCT/EP1998/008232 patent/WO1999033072A1/en not_active Ceased
- 1998-12-17 JP JP2000525894A patent/JP2001527283A/en active Pending
- 1998-12-17 RU RU2000119040/02A patent/RU2203516C2/en not_active IP Right Cessation
- 1998-12-17 CN CN98813070A patent/CN1285950A/en active Pending
- 1998-12-17 KR KR1020007006979A patent/KR20010033478A/en not_active Ceased
- 1998-12-17 CA CA002315704A patent/CA2315704A1/en not_active Abandoned
- 1998-12-17 AU AU21622/99A patent/AU2162299A/en not_active Abandoned
- 1998-12-17 EP EP98965839A patent/EP1051715A1/en not_active Withdrawn
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102441488A (en) * | 2011-09-06 | 2012-05-09 | 北京交通大学 | Slide-type gas-liquid interface jigging magnetic separation controllable device |
| CN102441488B (en) * | 2011-09-06 | 2013-07-31 | 北京交通大学 | Slide-type gas-liquid interface jigging magnetic separation controllable device |
| CN110495080A (en) * | 2017-04-14 | 2019-11-22 | 开利公司 | Increased motor winding inductance |
| US11368078B2 (en) | 2017-04-14 | 2022-06-21 | Carrier Corporation | Electrical machine winding inductance enhancement |
| CN107195419A (en) * | 2017-08-02 | 2017-09-22 | 新疆大学 | Ethylene glycol magnetic fluid and preparation method thereof |
| CN108037700A (en) * | 2017-12-13 | 2018-05-15 | 杭州电子科技大学 | A kind of magnetic current body controlling means |
Also Published As
| Publication number | Publication date |
|---|---|
| DE19758350C1 (en) | 1999-03-11 |
| AU2162299A (en) | 1999-07-12 |
| CA2315704A1 (en) | 1999-07-01 |
| EP1051715A1 (en) | 2000-11-15 |
| WO1999033072A1 (en) | 1999-07-01 |
| KR20010033478A (en) | 2001-04-25 |
| JP2001527283A (en) | 2001-12-25 |
| RU2203516C2 (en) | 2003-04-27 |
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