11 results about "Magnetic transitions" patented technology

The invention discloses an electrochemical method for regulating and controlling the phase, resistance and magnetism of a two-dimensional layered material, and belongs to the field of two-dimensional transition metal chalcogenide. The electrochemical method comprises the steps that an electrode system is provided, the electrode system comprises a working electrode and a counter electrode, the working electrode comprises a two-dimensional layered material, the chemical formula of the two-dimensional layered material is MX2, M represents a transition metal element, and X represents a group VI element where a sulfur element is located; providing an electrolyte, wherein the electrolyte is a soluble salt solution containing magnetic transition metal ions; the electrode system is placed in the electrolyte, and under the action of an external electric field, the magnetic transition metal ions are embedded and separated from the two-dimensional layered material, so that the phase, the resistance and the magnetism of the two-dimensional layered material are synergistically regulated and controlled. According to the technology, magnetic transition metal ions are driven by an electric field to be reversibly embedded into and separated from a two-dimensional layered material, so that the phase, the resistance and the magnetism of the two-dimensional layered material are synergistically and dynamically regulated and controlled, and the problems that the traditional external field regulation and control dimension is single, and intrinsic physical property coupling change is difficult to realize are solved. And multi-physical-property combined regulation and control is realized by adjusting an electric field, so that a basis is provided for application of the material in the fields of photoelectric devices, magnetoelectric storage, sensors and the like.

The application provides a permanent magnet synchronous motor weak magnetic transition area smooth transition method and system based on a reference voltage adaptive reduction, and belongs to the field of permanent magnet synchronous motor control. The method solves the problem of torque fluctuation caused by voltage overshoot in the existing voltage closed-loop weak magnetic control with a fixed reference voltage. The method comprises the following steps: obtaining a theoretical maximum torque according to a preset current limit value by simultaneously solving a torque equation and a current constraint equation; calculating torque ratio parameters and speed ratio parameters in real time; calculating a reference voltage adaptive coefficient based on an adaptive smooth transition algorithm; multiplying the adaptive coefficient by the inscribed circle voltage of an inverter to dynamically adjust the reference value of the voltage closed loop, so that smooth control of the weak magnetic transition area is realized. The method is mainly used in the fields of electric aircrafts, electric vehicles and robots.

The present technology includes semiconductor devices and methods with improved contact resistivity. Semiconductor devices include a substrate base, a silicon oxide disposed on the base defining one or more features, a non-magnetic transition-metal doped contact silicide layer disposed on the substrate in the one or more features, and at least a first metal layer. The non-magnetic transition-metal doped contact silicide layer includes a non-magnetic transition-metal, a first metal, and a silicon containing compound, and includes greater than or about 8.0 E+13 per cm2 non-magnetic transition-metal atoms. The first metal layer includes the first metal and overlies the non-magnetic transition-metal doped contact silicide layer.

The present technology includes semiconductor devices and methods with improved contact resistivity. Semiconductor devices include a substrate base, a silicon oxide disposed on the base defining one or more features, a non-magnetic transition-metal doped contact silicide layer disposed on the substrate in the one or more features, and at least a first metal layer. The non-magnetic transition-metal doped contact silicide layer includes a non-magnetic transition-metal, a first metal, and a silicon containing compound, and includes greater than or about 8.0 E+13 per cm2 non-magnetic transition-metal atoms. The first metal layer includes the first metal and overlies the non-magnetic transition-metal doped contact silicide layer.

The invention discloses a preparation method of a special high-quality LaCoO3-delta single crystal with a magnetic transition property. The preparation method comprises the following steps: performing dewatering sintering on La2O3 powder; putting the pretreated La2O3 powder and Co3O4 powder into a mortar according to a combination reaction ratio, and uniformly grinding; the powder is poured into a customized stainless steel mold and pressed into a sheet shape under the pressure of 1.4 T; placing the flaky sample in a crucible boat, and sintering in a high-temperature furnace at a set temperature of 1050 DEG C for 50 hours; preparing a precursor charge bar, namely uniformly grinding the pressed sample powder which is sintered and cooled to room temperature, putting the pressed sample powder into a latex mold, and carrying out compression molding under high pressure of an isostatic press; sintering the prepared precursor charge bar in a high-temperature furnace to form a polycrystalline charge bar; placing the polycrystal bar in a high-precision optical floating zone method single crystal furnace for single crystal growth; and the bright, glossy and high-quality LaCoO3-delta single crystal is successfully grown by adopting an optical floating zone method.

This invention discloses a core-shell structured amorphous / nanocrystalline biphase rare-earth-based magnetic refrigeration material, its preparation method, and its applications, belonging to the field of magnetic refrigeration technology. The chemical formula of this material is Gd. x M y Cu z Where 90≤x≤95, 1≤y≤5, 1≤z<5, and y>z, and M is selected from any one of Fe, Co, and Ni; its microstructure is a core-shell dual-phase structure consisting of an amorphous shell encapsulating a nanocrystalline nucleus. This material exhibits more than two magnetic transition temperatures, and its magnetic entropy change curve shows two / three peaks, with a maximum magnetic entropy change of 5.4–6.9 J kg under a 5 T applied magnetic field. ‑1 K ‑1 The magnetic refrigeration temperature range reaches 106-220 K, with a relative refrigeration capacity of 731-1265 J / kg. This material combines high magnetic entropy change, wide refrigeration temperature range, excellent chemical stability, and high service reliability, making it suitable for widespread application as a magnetic refrigerant in the field of green solid-state refrigeration.

The invention belongs to the technical field of adsorbent materials, and particularly relates to a magnetic transition metal sulfide adsorption material and a preparation method and application thereof. The preparation method comprises the following steps: by taking Mo-MOF as a precursor, calcining a sulfur source and the Mo-MOF at 1000-1100 DEG C under a protective atmosphere, carbonizing a ligand in the Mo-MOF to form a porous carbon matrix, performing a vulcanization reaction on the sulfur source and Mo < 3 + > to form MoS2 particles, and embedding the MoS2 particles into the porous carbon matrix to obtain MoS2 / C; a chemical coprecipitation method is adopted, Fe3O4 magnetic nanoparticles are loaded on the surface of MoS2 / C, and the magnetic transition metal sulfide adsorption material is obtained. The prepared magnetic transition metal sulfide adsorption material can efficiently and selectively adsorb and reduce Au < 3 + > in a water body, rapid separation can be carried out through magnetism, and resource recycling of gold is achieved.

The present invention discloses a method for preparing a magnetic electrode based on improving the electro-Fenton efficiency. The present invention belongs to the field of environmental functional materials. By preparing a magnetic transition metal electrode, its electronic structure is regulated, thereby achieving the regulation of selectivity and reaction activity. At the same time, the inherent ferromagnetism of the transition metal electrode material itself and the paramagnetic properties of O2 are utilized to introduce an external magnetic field to magnetize the magnetic electrode, thereby improving mass transfer and reaction activity. It is possible to achieve coordinated regulation of 2-electron ORR selectivity, reaction activity and O2 mass transfer. By achieving efficient synthesis of H2O2, the reaction rate of the rate-limiting step is increased, thereby solving the problem of low overall efficiency of the electro-Fenton system, achieving the lowest cost, while improving sewage treatment efficiency and reducing process operation energy consumption.

The application belongs to the technical field of semiconductor thin film materials, and particularly relates to a diluted magnetic semiconductor thin film for In-based semiconductor materials. 2‑x M x O3, the doping element is a non-magnetic transition metal M, which is one or more of Fe, Mn, Co or Ni, and 0 < x < 0.1. The application adopts a laser pulse deposition technology (PLD) based on a ceramic target material to prepare an InO-based diluted magnetic semiconductor thin film with room-temperature ferromagnetism by means of a transition metal ion as a donor doping mode. The PLD technology of the application can incorporate a high proportion of transition metal ions into the InO lattice, and a large number of lattice defects can be introduced by controlling the deposition conditions, so that a ferromagnetic thin film material higher than room temperature is induced, which can be applied to spin electronic devices.

The application discloses a kind of battery module active and passive combination ejection structure, energy storage system and method, it is related to battery energy storage safety structure technical field, based on the active and passive combination battery electric / thermal magnetic induction ejection structure design of electromagnetic induction and soft magnetic iron material specific temperature under magnetic transition feature, through electrical and mechanical linkage, the safety of battery pack ejection is guaranteed, active trigger is monitored voltage, temperature and other abnormal information by BMS, and the instruction execution ejection is issued by system general control;Passive trigger utilizes the magnetic transition characteristics of soft magnetic iron at specific temperature (thermal runaway characteristic temperature), without BMS instruction, can be automatically triggered, using the trigger mechanism of active and passive combination solves the limitation of only relying on BMS active control in prior art, through two kinds of mechanism complement each other, even if BMS monitoring is inaccurate or sensor failure, still can be isolated fault battery pack by passive trigger, greatly reduce the security risk.

The invention discloses a preparation method of a directionally-arranged boron nitride-based self-expanding epoxy flame-retardant material. The preparation method comprises the following steps: (1) preparing a BN / Fe3O4-coated PATP nano composite flame retardant; (2) preparing the directionally-arranged boron nitride-based self-expansion epoxy flame-retardant material; according to the invention, the flame retardance is improved by utilizing the heat transfer anisotropic characteristic after oriented arrangement of BN; an ATP monomer expanding agent and a magnetic transition metal oxide (ferroferric oxide) are used for synergistically modifying BN, so that a way is provided for magnetically inducing oriented arrangement of BN nanosheets, and meanwhile, the effect of expanding a carbon layer of a non-expansive resin matrix is achieved; in the combustion process, the directionally-arranged boron nitride-based self-expanding epoxy flame-retardant material has the lowest PHRR (833.92 kW / m < 2 >), THR (24.35 MJ / m < 2 >), PSPR (0.121 m < 2 > / s) and TSP value (3.6 m < 2 >), and shows the best flame retardance and smoke suppression effect.