Disclosed herein is a method comprising disposing a container containing a metal and/or ferromagnetic solid and abrasive particles in a static magnetic field; where the container is surrounded by an induction coil; activating the induction coil with an electrical current, to heat up the metallic or ferromagnetic solid to form a fluid; generating sonic energy to produce acoustic cavitation and abrasion between the abrasive particles and the container; and producing nanoparticles that comprise elements from the container, the metal and/or the ferromagnetic solid and the abrasive particles. Disclosed herein too is a composition comprising first metal or a first ceramic; and particles comprising carbides and/or nitrides dispersed therein. Disclosed herein too is a composition comprising nanoparticles comprising chromium carbide, iron carbide, nickel carbide, γ-Fe and magnesium nitride.

A method for preparation of a magnetic liquid metal includes: 1) placing A parts by weight of a liquid metal in a container; 2) placing B parts by weight of a metal powder in the container; 3) adding an acidic solution into the container until the liquid metal and the metal powder are submerged; 4) stirring until the liquid metal and the metal powder are sufficiently mixed; and 5) adding water for cleaning the acidic solution, and to obtain the magnetic liquid metal by removing the acidic solution. The viscosity and stiffness of the prepared magnetic liquid metal can quickly respond to the stimulus from an applied magnetic field, and a reversible change from liquid to semisolid or solid exists. With a change in magnetic field strengths, the Young's modulus can be regulated in a range from the level of kPa to the level of MPa.

A method of forming magnetically permeable material is provided. The method includes introducing magnetorheological (MR) fluid including one or more of magnetically permeable particles, fibers and fillers suspended in a curable liquid into a cavity, driving the magnetically permeable particles, fibers and/or fillers in the MR fluid into flux line formations and curing the curable liquid of the MR fluid during the driving to lock the flux line formations in place.

Disclosed herein is a method comprising disposing a container containing a metal and/or ferromagnetic solid and abrasive particles in a static magnetic field; where the container is surrounded by an induction coil; activating the induction coil with an electrical current, to heat up the metallic or ferromagnetic solid to form a fluid; generating sonic energy to produce acoustic cavitation and abrasion between the abrasive particles and the container; and producing nanoparticles that comprise elements from the container, the metal and/or the ferromagnetic solid and the abrasive particles. Disclosed herein too is a composition comprising first metal or a first ceramic; and particles comprising carbides and/or nitrides dispersed therein. Disclosed herein too is a composition comprising nanoparticles comprising chromium carbide, iron carbide, nickel carbide, γ-Fe and magnesium nitride.

A composite magnetic material includes a powder and a resin. The powder has a main component containing Fe or Fe and Co. An average minor axis length in primary particles of the powder is 100 nm or less. A point satisfying (X, Y)=(σ/A.sub.v (%), (A.sub.v-σ)) on an XY coordinate plane is present within a region (including a boundary) surrounded by three points α(24.5, 6.7), β(72.0, 1.2), and γ(24.5, 1.2), in which an average of aspect ratios in the primary particles of the powder is set to A.sub.v, and a standard deviation of the aspect ratios in the primary particles of the powder is set to σ.

A magnetic position sensor having at least one magnetic field sensor including a solidified layer of GMR nanowire carrier fluid formed on a substrate material. The solidified layer of carrier fluid has (i) discrete GMR nanowires each having a diameter of less than about 0.5 um and a length less than about 250 um; and (ii) a concentration of GMR nanowires in the dried layer between about 0.001 and about 10 percent by weight of the solution. The position sensor further includes a detection circuit capable of detecting a change in resistance of the magnetic field sensor.

A magneto-rheological elastomer composition (10) includes a matrix resin (12) and a magnetic powder (11). The magnetic powder (11) is contained in an amount of 30 to 70% by volume based on 100% by volume of the composition. The magneto-rheological elastomer composition (10) has an Asker C hardness of 5 to 60 as determined by the Standard SRIS0101 of the Society of Rubber Science and Technology, Japan. The average particle size of the magnetic powder is preferably 2 to 500 μm, and the matrix resin is preferably an organopolysiloxane. The storage modulus of the magneto-rheological elastomer composition preferably changes by five times or more upon application of a magnetic force with a magnetic flux density of 200 mT. Thus, the present invention provides a magneto-rheological elastomer composition that greatly changes its storage modulus upon application of magnetism, a method for producing the same, and a vibration absorbing device including the same.

Electromagnetically-induced cement concrete crack self-healing diisocyanate microcapsules include raw materials, in parts by weight, comprising 15-55 parts of petroleum resin, 5-10 parts of paraffin, 5-10 parts of polyethylene wax, 3-10 parts of magnetic iron powder and 20-67 parts of diisocyanate. The diisocyanate microcapsules use the diisocyanate as a core material, and the petroleum resin/paraffin/polyethylene wax/magnetic iron powder mixture as the shell of the capsule. When micro cracks occur in the concrete, the crack propagation can break partial of the microcapsule inside, the diisocyanate inside the microcapsules flows out and diffuses into the crack and is subjected to a solidifying reaction with water in the concrete, so that the crack is repaired in time; and for the microcapsules that are not broken by cracks, external electromagnetic field can be applied to melt the shell to release the diisocyanate inside, thereby diffusing into cracks and solidify with water to repair them.

Provided is a magnetorheological fluid having excellent long-term dispersion stability of magnetic particles and a large maximum change of yield stress under magnetic field application conditions. Also provided is a device having excellent long-term stable drivability and mechanism reliability. The magnetorheological fluid contains magnetic particles, resin particles, and a dispersion medium, wherein the proportion constituted by the mass of the magnetic particles relative to the total mass of the magnetorheological fluid is 35 mass % to 95 mass %, the proportion constituted by the mass of the resin particles relative to the total mass of the magnetorheological fluid is 0.3 mass % to 20 mass %, and the average particle diameter of the resin particles is 20 nm to 1,500 nm. This magnetorheological fluid is used in the device.

Described herein is a system to remote-control magnetic actuation of dynamic cell culture. The systems described herein can include a porous, magnetic, elastomeric construct. The porous, magnetic, elastomeric construct can be formed from a composite including a biocompatible elastomer and a population of magnetic particles dispersed within the biocompatible elastomer.