Abstract: Example nanoparticles may include an iron-based core, and a shell. The shell may include a non-magnetic, anti-ferromagnetic, or ferrimagnetic material. Example alloy compositions may include an iron-based grain, and a grain boundary. The grain boundary may include a non-magnetic, anti-ferromagnetic, or ferrimagnetic material. Example techniques for forming iron-based core-shell nanoparticles may include depositing a shell on an iron-based core. The depositing may include immersing the iron-based core in a salt composition for a predetermined period of time. The depositing may include milling the iron-based core with a salt composition for a predetermined period of time. Example techniques for treating a composition comprising core-shell nanoparticles may include nitriding the composition.

Abstract: The disclosure describes techniques for forming nanoparticles including Fe16N2 phase. In some examples, the nanoparticles may be formed by first forming nanoparticles including iron, nitrogen, and at least one of carbon or boron. The carbon or boron may be incorporated into the nanoparticles such that the iron, nitrogen, and at least one of carbon or boron are mixed. Alternatively, the at least one of carbon or boron may be coated on a surface of a nanoparticle including iron and nitrogen. The nanoparticle including iron, nitrogen, and at least one of carbon or boron then may be annealed to form at least one phase domain including at least one of Fe16N2, Fe16(NB)2, Fe16(NC)2, or Fe16(NCB)2.

Abstract: The disclosure describes techniques for forming hard magnetic materials including ??-Fe16N2 using chemical vapor deposition or liquid phase epitaxy and hard materials formed according to these techniques. A method comprises heating an iron source to form a vapor comprising an iron-containing compound; depositing iron from the vapor comprising the iron-containing compound and nitrogen from a vapor comprising a nitrogen-containing compound on a substrate to form a layer comprising iron and nitrogen; and annealing the layer comprising iron and nitrogen to form at least some crystals comprising ??-Fe16N2.

Abstract: A permanent magnet may include a Fe16N2 phase in a strained state. In some examples, strain may be preserved within the permanent magnet by a technique that includes etching an iron nitride-containing workpiece including Fe16N2 to introduce texture, straining the workpiece, and annealing the workpiece. In some examples, strain may be preserved within the permanent magnet by a technique that includes applying at a first temperature a layer of material to an iron nitride-containing workpiece including Fe16N2, and bringing the layer of material and the iron nitride-containing workpiece to a second temperature, where the material has a different coefficient of thermal expansion than the iron nitride-containing workpiece. A permanent magnet including an Fe16N2 phase with preserved strain also is disclosed.

Abstract: A bulk permanent magnetic material may include between about 5 volume percent and about 40 volume percent Fe16N2 phase domains, a plurality of nonmagnetic atoms or molecules forming domain wall pinning sites, and a balance soft magnetic material, wherein at least some of the soft magnetic material is magnetically coupled to the Fe16N2 phase domains via exchange spring coupling. In some examples, a bulk permanent magnetic material may be formed by implanting N+ ions in an iron workpiece using ion implantation to form an iron nitride workpiece, pre-annealing the iron nitride workpiece to attach the iron nitride workpiece to a substrate, and post-annealing the iron nitride workpiece to form Fe16N2 phase domains within the iron nitride workpiece.

Abstract: The disclosure describes techniques for forming nanoparticles including Fe16N2 phase. In some examples, the nanoparticles may be formed by first forming nanoparticles including iron, nitrogen, and at least one of carbon or boron. The carbon or boron may be incorporated into the nanoparticles such that the iron, nitrogen, and at least one of carbon or boron are mixed. Alternatively, the at least one of carbon or boron may be coated on a surface of a nanoparticle including iron and nitrogen. The nano particle including iron, nitrogen, and at least one of carbon or boron then may be annealed to form at least one phase domain including at least one of Fe16N2, Fe16(NB)2, Fe16(NC)2, or Fe16(NCB)2.

Abstract: Example nanoparticles may include an iron-based core, and a shell. The shell may include a non-magnetic, anti-ferromagnetic, or ferrimagnetic material. Example alloy compositions may include an iron-based grain, and a grain boundary. The grain boundary may include a non-magnetic, anti-ferromagnetic, or ferrimagnetic material. Example techniques for forming iron-based core-shell nanoparticles may include depositing a shell on an iron-based core. The depositing may include immersing the iron-based core in a salt composition for a predetermined period of time. The depositing may include milling the iron-based core with a salt composition for a predetermined period of time. Example techniques for treating a composition comprising core-shell nanoparticles may include nitriding the composition.

Abstract: Techniques are disclosed concerning applied magnetic field synthesis and processing of iron nitride magnetic materials. Some methods concern casting a material including iron in the presence of an applied magnetic field to form a workpiece including at least one iron-based phase domain including uniaxial magnetic anisotropy, wherein the applied magnetic field has a strength of at least about 0.01 Tesla (T). Also disclosed are workpieces made by such methods, apparatus for making such workpieces and bulk materials made by such methods.

Abstract: A method may include annealing a material including iron and nitrogen in the presence of an applied magnetic field to form at least one Fe16N2 phase domain. The applied magnetic field may have a strength of at least about 0.2 Tesla (T).

Abstract: A method may include annealing a material including iron and nitrogen in the presence of an applied magnetic field to form at least one Fe16N2 phase domain. The applied magnetic field may have a strength of at least about 0.2 Tesla (T).

Abstract: Dihydrogen metaphosphate can be synthesized via protonation, and can react with a dehydrating agent to afford tetrametaphosphate anhydride. A monohydrogen tetrametaphosphate organic ester can be derived from the anhydride. A metal tetrametaphosphate complex can be prepared using a metal salt and a dihydrogen tetrametaphosphate.

Abstract: An ultra-high sensitivity dual-gated biosensor based on an MOS transistor, which is applicable to detection of a series of early tumors. The sensor is prepared and processed by using SOI wafers, and a unique dual-gated structure is realized by ion implantation technique. The sensor is prepared by an ultraviolet lithography combined with an NLD etching method, realizing trace, instant and marker-free detection of tumor markers. The method detects a change in capacitance in the channel during binding of antigen antibodies. The detection method involved in the invention is more stable and strong in anti-interference, can meet the demands in the aspect of detection range and sensitivity, and especially has extremely outstanding detection sensitivity, and can detect a sample with a lowest concentration in the range of 1 fg/ml˜1 ng/ml.

Abstract: A bulk permanent magnetic material may include between about 5 volume percent and about 40 volume percent Fe16N2 phase domains, a plurality of nonmagnetic atoms or molecules forming domain wall pinning sites, and a balance soft magnetic material, wherein at least some of the soft magnetic material is magnetically coupled to the Fe16N2 phase domains via exchange spring coupling. In some examples, a bulk permanent magnetic material may be formed by implanting N+ ions in an iron workpiece using ion implantation to form an iron nitride workpiece, pre-annealing the iron nitride workpiece to attach the iron nitride workpiece to a substrate, and post-annealing the iron nitride workpiece to form Fe16N2 phase domains within the iron nitride workpiece.

Abstract: This disclosure describes various examples of spintronic temperature sensors. The example temperature sensors may be discrete or used to adaptively control operation of a component such as an integrated circuit (IC). In one example, an electronic device comprises a spintronic component configured such that the conductance of the spintronic component is based on sensed temperature. In one example, circuitry coupled to the spintronic component is configured to generate an electrical signal indicative of the sensed temperature based on the conductance of the spintronic component.

Abstract: The disclosure discloses a method for preparing a ??-Fe4N soft magnetic material by using liquid nitrogen through high-speed ball milling, and belongs to the field of the soft magnetic material. According to the method of the disclosure, high energy in the liquid nitrogen is used for obtaining a nanometer material FexN with a nitrogen atom supersaturation degree through cryogrinding. At a low temperature, the material is very brittle, and a surface volume ratio is very high, so that a content of nitrogen atoms adsorbed on a surface of a sample is as high as 22%. Through 300° C. post-annealing, ??-Fe4N is directly obtained from ?-Fe through phase change, so that a nanometer crystal ??-Fe4N soft magnetic material is prepared.

Abstract: A bulk permanent magnetic material may include between about 5 volume percent and about 40 volume percent Fe16N2 phase domains, a plurality of nonmagnetic atoms or molecules forming domain wall pinning sites, and a balance soft magnetic material, wherein at least some of the soft magnetic material is magnetically coupled to the Fe16N2 phase domains via exchange spring coupling. In some examples, a bulk permanent magnetic material may be formed by implanting N+ ions in an iron workpiece using ion implantation to form an iron nitride workpiece, pre-annealing the iron nitride workpiece to attach the iron nitride workpiece to a substrate, and post-annealing the iron nitride workpiece to form Fe16N2 phase domains within the iron nitride workpiece.

Abstract: Techniques are disclosed for milling an iron-containing raw material in the presence of a nitrogen source to generate anisotropically shaped particles that include iron nitride and have an aspect ratio of at least 1.4. Techniques for nitridizing an anisotropic particle including iron, and annealing an anisotropic particle including iron nitride to form at least one ??-Fe16N2 phase domain within the anisotropic particle including iron nitride also are disclosed. In addition, techniques for aligning and joining anisotropic particles to form a bulk material including iron nitride, such as a bulk permanent magnet including at least one ??-Fe16N2 phase domain, are described. Milling apparatuses utilizing elongated bars, an electric field, and a magnetic field also are disclosed.

Abstract: The disclosure describes multilayer hard magnetic materials including at least one layer including ??-Fe16N2 and at least one layer including ??-Fe16(NxZ1-x)2 or a mixture of ??-Fe16N2 and ??-Fe16Z2, where Z includes at least one of C, B, or O, and x is a number greater than zero and less than one. The disclosure also describes techniques for forming multilayer hard magnetic materials including at least one layer including ??-Fe16N2 and at least one layer including ??-Fe16(NxZ1-x)2 or a mixture of ??-Fe16N2 and ??-Fe16Z2 using chemical vapor deposition or liquid phase epitaxy.

Abstract: Techniques are disclosed for milling an iron-containing raw material in the presence of a nitrogen source to generate anisotropically shaped particles that include iron nitride and have an aspect ratio of at least 1.4. Techniques for nitridizing an anisotropic particle including iron, and annealing an anisotropic particle including iron nitride to form at least one a?-Fe16N2 phase domain within the anisotropic particle including iron nitride also are disclosed. In addition, techniques for aligning and joining anisotropic particles to form a bulk material including iron nitride, such as a bulk permanent magnet including at least one a?-Fe16N2 phase domain, are described. Milling apparatuses utilizing elongated bars, an electric field, and a magnetic field also are disclosed.