228 results about "Electrical resistivity and conductivity" patented technology

A medium-strength and high-conductivity aluminum alloy sheet and its preparation method, which relate to an aluminum alloy sheet and its preparation method. The purpose of the present invention is to solve the technical problem that when other alloying elements are added to existing aluminum alloys to improve the mechanical properties of the alloy, its electrical conductivity will be sacrificed. The medium-strength and high-conductivity aluminum alloy sheet includes the following components by weight percentage: Mg: 0.45-0.53%, Si: 0.4-0.46%, Cu: 0.1-0.5%, Fe≤0.16%, Zn≤0.01%, Mn≤0.03%, Cr≤0.02%, and the balance is impurities and Al. Method: First, prepare an aluminum alloy ingot; second, perform heat treatment; third, perform rolling; fourth, perform solution aging treatment. The electrical conductivity of the medium-strength and high-conductivity aluminum alloy sheet prepared by the present invention is above 53% IACS, while the hardness is higher than 75 HV and the tensile strength is higher than 187 MPa. The present invention can obtain a medium-strength and high-conductivity aluminum alloy sheet.

The invention discloses a pulsed eddy current-based overhead ground wire corrosion detection method and system. The method comprises the following steps: acquiring an eddy current detection signal output by an annular pulsed eddy current sensor mounted on an overhead ground wire; according to the eddy current detection signal, obtaining a time domain characteristic value for representing the corrosion degree of the ground wire; the time domain characteristic value comprises a time domain characteristic value delta Smax of the magnetic conductivity variable quantity or / and a time domain characteristic value T delta S of the conductivity variable quantity; and comparing the time domain characteristic value delta Smax of the magnetic conductivity variable quantity or / and the time domain characteristic value T delta S of the conductivity variable quantity with a corresponding preset standard threshold value, and judging the corrosion degree of the overhead ground wire according to a comparison result. The method has the advantages of high detection efficiency, accurate detection and the like.

The invention belongs to the technical field of concrete detection, and particularly relates to a porosity electromagnetic nondestructive testing method, medium and system capable of eliminating moisture influence, and the method comprises the following steps: preparing test pieces with different moisture contents by adopting a to-be-tested medium, and obtaining the porosity of each test piece; obtaining the dielectric constant and the conductivity of each test piece through a ground penetrating radar, and constructing a data set containing the dielectric constant, the conductivity and the porosity; deriving a dielectric model under a water-containing condition and a conductivity model under an unsaturated state, and simultaneously eliminating water content parameters in the models to obtain a porosity detection model containing unknown parameters; the data set is substituted into the porosity detection model for fitting, and the porosity detection model which is not affected by moisture is obtained. Compared with the prior art, the method has the advantages that the problem that in the prior art, the GPR testing of the concrete porosity is easily interfered by moisture is solved, and the influence of moisture on calculation in electromagnetic nondestructive testing is eliminated.

Method and systems are provided that characterize a geological formation, which involve collecting or obtaining electrical signal data that results from interaction of electrical signals with the formation. The electrical signal data is processed to determine data characterizing relative permittivity and conductivity of the formation. The data characterizing relative permittivity and conductivity of the formation are used as inputs to models to determine data characterizing water saturation of the formation, particularly useful in formation evaluation and reservoir saturation dynamic monitoring in fresh water and mixed salinity environments.

The invention provides a composite positive electrode material and a preparation method and application thereof, the composite positive electrode material comprises a matrix and a carbon coating layer on the surface of the matrix, and the matrix comprises a porous LMFP material; the porous LMFP material comprises doped metal elements, and holes of the porous LMFP material comprise a lithium supplement agent. Doping elements in the composite positive electrode material can improve the stability of a crystal structure and reduce high-temperature storage and cyclic gas production, and the lithium supplement agent in the porous LMFP material can prolong the cycle life of the material and can be decomposed to form pores again after first-time charging, so that an electrolyte can enter the interior of material particles, and the service life of the material is prolonged. And the carbon coating layer can improve the conductivity of the material and reduce the polarization impedance of the material, and meanwhile, the processing problems that residual alkali on the surface of the lithium supplementing agent reacts with a glue solution, so that slurry is gelled and the like can be avoided.

The utility model provides an antenna and electronic equipment, and the antenna comprises a resonant ring which comprises an annular base part with a first opening; and the first periodic structure and the second periodic structure are both located in a space defined by the annular base part and are both connected with the resonant ring. Through the arrangement, a metamaterial structure is formed, the electrical performance of the antenna can be improved, the physical characteristics such as negative magnetic conductivity and negative electrical conductivity can be realized, the performance of the antenna can be improved, and the wiring area and the occupied space of the antenna can be reduced.

A closing resistor quality detection modeling method based on the equivalent destruction principle, in which a closing resistor model is established based on the electrical parameters and geometric model of the closing resistor, the closing resistor conductivity, thermal expansion coefficient, Young's modulus, density and specific heat capacity of the closing resistor model are set, and a closing resistor equivalent destruction simulation numerical model is established based on the closing resistor model and the electrical parameters of the closing resistor, the closing resistor equivalent destruction simulation numerical model includes an impulse current waveform, a contact mode between closing resistors and a temperature characteristic of the closing resistor, which are set in sequence, and an impulse current injection into the closing resistor equivalent destruction simulation numerical model is formed based on the equivalent modeling of the closing resistor equivalent destruction simulation numerical model, and the limit value of the impulse current that the closing resistor can withstand is calculated to simulate and optimize the closing resistor equivalent destruction simulation numerical model.

The invention provides a force thermal electric field coupling method based on an inclined crown spring connector, and belongs to the field of electric connector design and optimization analysis, and the method specifically comprises the following steps: S1, building a single-terminal parameterization CAE model of an inclined crown spring large-current connector, material attribute setting, grid division, contact pair definition, boundary condition and solver configuration are completed through an APDL language; s2, executing transient mechanical field simulation, and extracting normal contact force, geometric deformation and contact area of each contact at the moment when the pin is completely inserted; s3, based on the Hertz contact theory, calculating a contact resistance theoretical value according to the normal contact force of each contact, and deducing the contact conductivity and the contact heat conductivity; and S4, reconstructing a reed geometric model according to a mechanical field deformation result, and fitting the shape of the contact into an ellipse or a circle according to the contact area. The method is used for solving the problem that coupling simulation convergence is difficult due to a complex structure, and the multi-physics field coupling calculation difficulty is reduced.

A high performance die castable aluminum alloy is described, wherein the aluminum alloy is characterized as having a high yield strength and high conductivity compared to conventional aluminum alloys, and also a high flowability and low susceptibility to hot tearing when die cast. The aluminum alloy may contain 4-6 wt. % nickel, a yield strength of at least about 90 MPa, and an electrical conductivity of at least about 48% IACS.

A milk-flow rate (Q) of a fluid comprising milk or a mixture of milk and gas through a conduit (165) is determined by a sensor device (140) with a measurement chamber (160) comprising a reference electrode pair (170) and first and second measurement electrode pairs (110, 120) that determine at least one electrical characteristic of the fluid(RD). Based thereon, a processing device (150) derives a conductivity (σ) and / or an impedance (Z) value of the fluid that passes through the measurement chamber (160) at each of the first and second measurement electrode pairs (110, 120). Based thereon, in turn, the processing device (150) repeatedly derives a milk-filling factor (FF) in measurement chamber (160) and a speed (v) of the fluid that passes through the measurement chamber (160) by comparing the conductivity (σ) and / or the impedance (Z) value of the fluid at each of the first and second measurement electrode pairs with the conductivity (σ) and / or the impedance (Z) value of the milk of the fluid at the reference electrode pair (170) and mapping a first series of values against a second series of values in a set of temporal windows. The first series of values comprises the values of the first test parameter in the set of temporal windows and the second series of values comprises the values of the second test parameter in the set of temporal windows. A trained neural network (180) repeatedly determines the milk-flow rate (Q) based on the milk-filling factor (FF) in the measurement chamber (160) and the speed of (v) the fluid that passes through the measurement chamber (160).

A conductive hydrogel fiber including a hydrogel network formed from a water-soluble hydrogel polymer and conductive fillers dispersed therein is provided. The hydrogel network includes a porous structure having nanofibrillar network walls, the surfaces of which are provided with interconnected crystallized nanofibrils formed by concentration and aggregation of the hydrogel polymer. The conductive hydrogel fiber exhibits high electrical conductivity, excellent tensile strength, large elongation at break, high toughness, and low swelling in water.

The invention relates to an in-hole transient electromagnetic response characteristic numerical simulation method based on a tunnel three-dimensional geoelectric model and an absorption boundary finite element method, and belongs to the technical field of geophysical exploration. The method comprises the following steps: constructing a tunnel full-space three-dimensional conductivity model; based on a Maxwell equation set, a vector potential and a scalar potential are introduced, a vector control equation of a transient electromagnetic field is derived in combination with Coulomb specifications, first-order absorption boundary conditions are established, and a weak form finite element equation is derived through a Galerkin weighted margin method; generating a global sparse matrix by utilizing spatial discretization and unstructured grid division, and performing iterative solution on the dynamic electromagnetic field by adopting a Newmark time discretization method; and simulating the transient electromagnetic response of geological anomalous bodies with different resistivity and the distance between the geological anomalous bodies and the receiving coil, and analyzing the attenuation characteristic and the geometric gravity center effect to obtain an electromagnetic response rule. The device can accurately simulate the electromagnetic response of abnormal bodies such as aquifers and faults in front of a tunnel face and around drill holes.

The invention discloses a device and a method for measuring fluid conductivity at high temperature and high pressure, and relates to the technical field of physical property measurement. The device for measuring the conductivity of the fluid at the high temperature and the high pressure comprises a pyrophyllite pressure transmission assembly, a heater, a lower electrode plate, an upper electrode plate and a polytetrafluoroethylene sample cavity, and can measure the conductivity of the fluid at different temperatures and pressures by combining with a multi-surface jacking press; the polytetrafluoroethylene sample cavity is arranged, and the characteristics of low cost and high chemical stability of polytetrafluoroethylene are applied, so that the measurement of the fluid conductivity under the high-temperature and high-pressure environment can be realized at lower cost, and the measurement of the fluid conductivity under the high-temperature and high-pressure environment in the earth can be simulated.

The purpose of the present invention is to provide a sandwich structure that has both excellent heat dissipation properties and excellent mechanical properties. In order to achieve this purpose, the sandwich structure of the present invention has the following structure. The sandwich structure includes a core member (I), and a fiber reinforced member (II) disposed on both sides of the core member (I), wherein the core member (I) includes a sheet-shaped heat conductive member (III) having an in-plane thermal conductivity of 300 W / m·K or more.

The invention discloses a sub-grid method and system based on electromagnetic thermal coupling, and the method comprises the steps: introducing a time domain finite difference sub-grid algorithm in the field of an electromagnetic algorithm into a multi-physical field, and delimiting a sub-grid region based on a simulation model; calculating an electric field value in the coarse grid, and updating the electric field value of the coarse grid at the grid interface; introducing the electric field value of the coarse grid into the sub-grid, and carrying out updating calculation on the electromagnetic field value in the sub-grid; an electromagnetic loss equation is used as a heat source, a thermal field is updated and calculated, and a coarse grid thermal field value at the interface is corrected; according to the corresponding linear interpolation, linking the coarse grid thermal field value into the sub-grid; calculating the current conductivity value of the corresponding dielectric material according to the current temperature of each point in the current space, and updating the current conductivity value into the electromagnetic field parameters; and repeating the above steps until the set simulation time is satisfied, and finally obtaining the electromagnetic field distribution and the thermal field distribution when the simulation is finished, and the instantaneous change of the electromagnetic field and the temperature field of each point.

To provide a conductive polymer film remarkably excellent in electrical conductivity and a conductive polymer composition for providing the conductive polymer film.SOLUTION: The conductive polymer composition is used which contains 0.01-5 mass% of a specific polythiophene (A) and 0.016-0.5 mass% of carbon nanotubes (B). The polythiophene (A) can be produced by polymerizing a thiophene monomer represented by the following general formula (3) in water or an alcohol solvent in the presence of an oxidizing agent, and subsequently performing acid treatment if necessary.SELECTED DRAWING: None

The present invention discloses a method and system for quickly calculating full-time-domain ocean transient electromagnetic apparent conductivity. The method comprises: obtaining measured transient electromagnetic field response data; obtaining full-time-domain transient electromagnetic theoretical response by given conductivity initial value and given theoretical calculation time range according to a pre-established functional relationship between seabed medium conductivity and full-time-domain magnetic source transient electromagnetic response; calculating the time t corresponding to when the value of full-time-domain transient electromagnetic theoretical response is equal to the measured transient electromagnetic field response data by spline interpolation; m ; By time t m , combined with the given conductivity initial value, the full-time domain apparent conductivity parameters of the measured response are obtained according to the conductivity fast calculation formula. The method of the present invention is a qualitative interpretation method suitable for arbitrary emission waveforms, full time domain, full space, and multiple components. This method only requires one forward modeling, avoiding the time cost of multiple forward modeling calculations in traditional iterative methods, and is more suitable for marine transient electromagnetic data interpretation.

The invention relates to corrosion monitoring. A corrosion sensor is disclosed that includes a mixture of a corrosive material and a non-corrosive material, where the corrosive material and the non-corrosive material are electrically conductive, the corrosive material having a higher electrical conductivity than the non-corrosive material. An increase in resistance of the corrosion sensor provides an indication of corrosion upon exposure to a corrosive gas that corrodes the corrosive material.

Provided are an electromagnetic wave control element including a first patterned conductive layer, an insulating layer, and a layer containing a material of which conductivity changes with a voltage, and a manufacturing method of an electromagnetic wave control element.

The present invention relates to an electrode for use in an energy storage device, the electrode comprising an electron collector, an active material and an electrically conductive binder wherein the electrically conductive binder comprises a solution treated n-type electrically conductive polymer having an electrical conductivity of at least 100 S / cm.

The invention relates to the technical field of chemical production, and provides a method for evaluating the surface electrical property of titanium dioxide powder, which comprises the following steps: grinding and thermally treating titanium dioxide powder particles to obtain titanium dioxide powder with a standardized surface state; preparing a monovalent electrolyte solution, and measuring the basic conductivity sigma0 of the monovalent electrolyte solution at a preset temperature; preparing turbid liquid based on the electrolyte solution and the titanium dioxide powder with the standardized surface state, carrying out solid-liquid separation on the turbid liquid after dispersion treatment, and collecting clarified liquid; measuring the conductivity sigma1 of the clarified liquid at a preset temperature; calculating an equivalent parameter A = [k (sigma0-sigma1)] / c; the unit of sigma0 and sigma1 is mS / cm, c is the mass concentration of the turbid liquid, the unit is g / L, k is a coefficient of 100-1000 and is dimensionless, and the absolute value of the equivalent parameter A is used for quantitatively representing the surface electrical property of the titanium dioxide powder particles and is dimensionless. According to the scheme, direct and quantitative characterization of the intrinsic surface electrical property of the powder is realized.

The application belongs to the field of metallurgy, and provides a copper alloy and a preparation method thereof.The copper alloy comprises a copper matrix and high-entropy alloy nano precipitated phases distributed in the copper matrix, and the high-entropy alloy nano precipitated phases comprise iron elements, cobalt elements, nickel elements and chromium elements.The application introduces high-entropy alloys as nano precipitated phases into the copper matrix, and the obtained copper alloy simultaneously has high electrical conductivity and thermal conductivity, and strength and ductility.

This invention discloses a method for calculating the conductivity of a supercritical fluid system taking into account the quartz dissolution effect, belonging to the technical field of calculating the conductivity of solutions in supercritical fluid systems. This invention establishes a fluid conductivity model in a ternary system under the conditions of a temperature of 500-800°C, a pressure of 6-12 kbar, and a NaCl concentration of 0.01-0.4X NaCl. By introducing a quartz solubility correlation equation and combining it with an ion activity coefficient model, this method quantifies the nonlinear evolution of supercritical fluid conductivity at a microscopic level, thus addressing the problems existing in the prior art.

A circuit board 1A has the following features: an insulating layer 10 with a first main surface 10a and a second main surface 10b facing each other in the thickness direction; a first intermediate layer interconnect 31 and a second intermediate layer interconnect 32, which are provided to extend in the thickness direction through the same insulating layer 10 or different insulating layers 10; a first conductor layer 21, which is provided at the first main surface 10a of the insulating layer 10 and is connected to the first intermediate layer interconnect 31; a second conductor layer 22, which is provided at the second main surface 10b of the insulating layer 10 and is connected to the first intermediate layer interconnect 31; a third conductor layer 23, which is provided at the first main surface 10a of the insulating layer 10 and is connected to the second intermediate layer interconnect 32; andA fourth conductor layer 24 is provided on the second main surface 10b of the insulating layer 10 and is connected to the second interlayer connecting conductor 32. The first interlayer connecting conductor 31 comprises, in the thickness direction, a first part 31A and a second part 31B with a lower electrical conductivity than the first part 31A. One end part of the first part 31A is attached to the first conductor layer 21, and another end part of the first part 31A is attached to an end part of the second part 31B. Another end part of the second part 31B is attached to the second conductor layer 22. The second interlayer connecting conductor 32 comprises, in the thickness direction, a third part 32A and a fourth part 32B with a lower electrical conductivity than the third part 32A. One end part of the third part 32A is attached to the third conductor layer 21 and another end part of the third part 32A is attached to an end part of the fourthPart 32B is attached. Another end part of the fourth part 32B is attached to the fourth conductor layer 24. The relationships T1 < T2 and B1 / A1 > B2 / A2 are satisfied, where A1 is the height of the first part 31A, B1 is the height of the second part 31B, A2 is the height of the third part 32A, B2 is the height of the fourth part 32B, T1 is the height of the first interlayer connecting conductor 31, and T2 is the height of the second interlayer connecting conductor 32.

The present invention provides a method and system for detecting the compaction degree of construction leveling, which is applied to the field of measurement data processing. Based on the preset electromagnetic induction sensor of the roller, the present invention can detect the compaction degree during the construction process in real time, solving the problem that the traditional method relies on spot checks after the construction is completed and cannot adjust the construction parameters in time. By collecting electromagnetic parameters (such as conductivity, permittivity, permeability) and matching them with the compaction state of the construction ground, the soil compaction situation can be evaluated in real time. When it is found that the compaction is insufficient, the additional rolling times are automatically calculated, and the operation parameters of the roller are dynamically adjusted according to the compaction distribution heat map. This process not only improves the construction accuracy and efficiency, but also can avoid the situation of over-compaction or under-compaction, reducing rework and resource waste, providing real-time data feedback and automatic adjustment functions, realizing the intelligent management of the construction process, thereby greatly improving the construction quality and resource utilization rate.

This invention discloses a method for improving the toughness of annealed conjugated polymer films. The method includes: mixing a nucleating agent with a conjugated polymer, forming a film, and then annealing it to obtain a modified conjugated polymer film. This invention accelerates the crystallization of the conjugated polymer by adding a nucleating agent, effectively increasing the number of connecting molecules between crystalline regions within the film. The annealed film exhibits higher electrical conductivity and better toughness, even approaching the tensile properties of unmodified conjugated polymer films, thus solving the problem of good electrical properties but poor toughness in annealed conjugated polymer films.

To provide a composite material having high thermal conductivity and low electrical conductivity. [Solution] The composite material comprises dispersed materials with a thermal conductivity of 100 W / K·m or more and an insulator interposed between the dispersed materials. For example, the dispersed materials are aluminum-based metal powders. For example, the insulator is an oxide or resin whose glass transition point is equal to or lower than the melting point of the dispersed materials. For example, the electrical conductivity of the composite material is 0.5×10 6 S / m or less.

Provided is an additive for a stretchable and / or flexible electrically conductive ink, the additive comprising: small liquid molecules with a high dielectric constant; wherein the additive improves electrical conductivity of the stretchable and / or flexible electrically conductive ink, and wherein the stretchable and / or flexible electrically conductive ink comprises a binder and electrically conductive particles.

Provided is an alumina powder which has an α-phase content of 95% or more and has a 100% cumulative particle diameter (D100) of 1-20 µm in a volume-based particle size distribution, wherein: the carbon content of the alumina powder is 0.01-2 mass%; and the electrical conductivity of a dispersion that contains 10 parts by mass of the alumina powder, 20 parts by mass of ethanol, and 70 parts by mass of ion exchanged water is 20 µS / cm or less at 25°C. The alumina powder is produced by subjecting the surfaces of alumina particles to an acid treatment and subsequently coating the surfaces with a silane coupling agent. As a result, the present invention provides: a sealant which has excellent fluidity and excellent thermal conductivity; and an alumina powder which is used for the sealant.