1032 results about "Conductivity" patented technology

The invention discloses a thick electrode with a good electrochemical performance. The electrode comprises a current collector and an electrode membrane containing active substances and conductive substances. With a thickness greater than 300 micrometers, the electrode membrane includes an internal membrane layer close to the current collector and an external membrane layer far from the current collector. The conductivity of the electrode membrane decreases from the internal membrane layer to the external membrane layer, while the porosity of the electrode membrane increases from the internal membrane layer to the external membrane layer. The internal membrane layer has great conductivity which can make electrons at the current collector entering or separating from the internal membrane layer rapidly. With great porosity, the external membrane layer can adsorb a lot of electrolyte, thus solving the problem of poor electrolyte wettability of thick electrodes. In addition, the invention also discloses a preparation method of a thick electrode with a good electrochemical performance.

The invention discloses a nitrogen and sulfur co-doped hierarchical porous carbon composite material, and a preparation method and an application thereof, and belongs to the technical field of supercapacitor electrode materials. A natural polymer material which is abundant in the nature, low in price and easy to obtain is used as a carbon source, graphene oxide is added to improve the conductivity, an activator and a doping agent are added in advance, and a general two-step technology (high-temperature carbonization and chemical activation) for preparing a carbon material is simplified into one-step high-temperature annealing, so that the carbon material with a high specific surface area and a hierarchical porous three-dimensional structure is obtained; and nitrogen and sulfur doping improves the electrochemical performances of the material. The composite carbon material has the advantages of high mass specific capacitance, excellent high-current rate capability, ultra-long cycle life,high mass energy density and high power density when used as a high-performance electrode material for a supercapacitor. The preparation method has the advantages of simplicity, feasibility, low requirements on reaction deices, environmental friendliness, and suitableness for industrial production.

This invention relates to a method of installation of an electrocoagulation (EC) system to remove contaminants from wastewater which includes the steps of: (i) measuring conductivity of the wastewater; (ii) from the result obtained in step (i) determining the number of electrically connected electrodes or unipolar electrodes required in the EC system for efficient removal of the contaminants, and (iii) from step (ii) assessing a range of current and/or voltage to be applied to an EC cell included in the EC system.

The method electromagnetically measures a pipe inner diameter ID and a pipe ratio of magnetic permeability to electrical conductivity μ₂/σ₂ by means of a measuring arrangement 1 comprising a transmitter coil 2 and a receiver coil 3, both coils being coaxial to and longitudinally spaced from each other, the measuring arrangement 1 being adapted to be positioned into the pipe CS and displaced through the pipe. The method comprises the steps of:

• • a1) exciting the transmitter coil 2 by means of a transmitter current I_i, the transmitter current having a first excitation frequency f₁,
  • a2) measuring a receiver voltage V_i at the receiver coil 3,
  • a3) determining a transimpedance V_i/I_i between the transmitter coil 2 and the receiver coil 3 based on the transmitter current I_i and the receiver voltage V_i, and determining a measurement ratio M_i based on said transimpedance,
  • b) repeating the excitation step a1), the measuring step a2), the transimpedance and the measurement ratio determination step a3) for at least a second excitation frequency f₂ so as to define a measurement ratio vector [M₁, M₂, . . . M_n],
  • c) calculating a prediction function vector [G₁, G₂, . . . G_n] based on the first and at least the second excitation frequency, a plurality of potential pipe ratio of magnetic permeability to electrical conductivity and a plurality of potential pipe inner diameter ID, and
  • d) applying a minimizing algorithm onto the measurement ratio vector [M₁, M₂, . . . M_n] and the prediction function vector [G₁, G₂, . . . G_n] and determining the pipe inner diameter and the pipe ratio of magnetic permeability to electrical conductivity corresponding to a maximum solution of the algorithm.

The invention relates to multi-parameter water quality monitoring integrated microarray electrodes and a preparation method. The invention is characterized in that the microarray electrodes are fabricated on an oxidized wafer. According to the invention, a Pt thin film is used as a substrate of the microarray electrodes, photosensitive polyimide is used as an insulation layer, electrode sites are exposed by using photoetching, and other parts of the microarray electrodes are insulated; an electrochemical modification method is used for electrodeposition of Ag/AgCl and IrOx films on bare electrodes so as to respectively form reference electrodes and pH test electrodes, thereby realizing determination of temperature, oxidation reduction potentials, conductivity and pH values. The preparation method comprises production of the micro-array electrodes, preparation of the Ag/AgCl reference electrodes and preparation of the pH electrodes. Integration and miniaturization of the microarray electrodes provided in the invention are convenient.

The invention discloses a method for positioning an artificial wetland clogging area through a resistivity curve. The method includes the steps that first, a direct-current resistivity symmetrical four-pole sounding device is arranged above an artificial wetland, and the apparent resistivity is measured according to the mode that the electrode spacing becomes bigger and bigger; second, a power supply positive electrode A, a power supply negative electrode B, a measurement electrode M and a measurement electrode N of the direct-current resistivity symmetrical four-pole sounding device are all arranged symmetrical about a measurement point, and the apparent resistivity (please see the formula in the specification) of the electrode spacing is calculated every time the power supply electrode spacing is changed; third, the measured apparent resistivity is subjected to inversion, and the resistivity depth measurement curve is drawn according to the resistivity values obtained through inversion; fourth, the non-clogging area of the artificial wetland has the low resistivity characteristic, the clogging area of the artificial wetland has the high resistivity characteristic, and on the resistivity depth measurement curve, the vertical spatial position of the clogging area in the measurement point is determined according to the changing characteristic of the resistivity value. According to the method, on the basis of the conductivity difference of dielectric, the artificial wetland clogging area can be positioned through the resistivity difference.

The invention relates to a method for manufacturing a porous flaky NiCo2O4 and grapheme composite capacitive material, and belongs to the field of nano composite material manufacturing. According to the method, a graphite oxide, cobalt nitrate and nickel nitrate are dissolved in deionized water in an ultrasonic mode and stirred, a certain amount of hexamethylene tetramine is added, a reflux reaction is carried out for 3-4 hours at the temperature of 90 DEG C, sediments are collected, the collected sediments are calcined in an air atmosphere for 2 hours at the temperature of 330 DEG C, and the porous flaky NiCo2O4 and grapheme nano composite material is obtained. In the manufactured porous flaky NiCo2O4 and grapheme composite capacitive material, porous flaky NiCo2O4 is completely attached to the surface of a grapheme piece. By means of the composite structure, conductivity of the material is improved, and the contact area of the material and an electrolyte solution is greatly improved, so that the composite material has high specific capacitance and good electrochemical stability and can be possibly used as a super-capacitor electrode material.

Methods and apparatus (50) are disclosed for accurately measuring low concentrations of boron in deionized water utilizing the chemical reaction of boric acid with a polyol by injecting very small plugs of concentrated polyol into streams of boron containing and non-boron containing water samples to produce an ionized acids product, and then measuring the conductivity difference (delta conductivity), corrected for interfering or extraneous factors which can effect conductivity, between such boron containing and non-boron containing samples using a conductivity and temperature detector (23).

Equipment for indicating a bed-wetting in a bed comprising a bed-wetter sheet and a measuring- and control system. A measuring circuit is furnished to test whether the electrode in the bed-wetter sheet are intact, and afterwards to measure the conductivity in the normal state between the two from each other electrically isolated electrodes whereby the conductivity between the two electrodes will fall drastically by a bed-wetting, human fluids containing salt being spread on the sheet, and indicate the bed-wetting. The measuring circuit is furnished to as a part of a routine to enter into a resting state whereby the measurement is performed with a prearranged fixed time interval.

Total organic carbon in an aqueous or gaseous sample is measured by admitting the sample and an oxidant gas to a cell transparent to plasma, establishing a relatively low energy plasma in the cell, and measuring the CO.sub.2 thus produced using FTIR, NDIR, or conductivity-based techniques.

An insulating coating ( 6 ) formed of engineering plastic with high heat resistance, high-pressure resistance, and chemical resistance is formed on a surface of a water-level detecting electrode part ( 3 ) of an electrode rod for detecting water-level ( 1 ) attached to penetrate a metal container ( 5 ) communicating with a boiler ( 7 ) and including an external power supply connecting terminal part ( 2 ) projecting outside the container ( 5 ) and the water-level detecting electrode part ( 3 ) projecting inside the container ( 5 ). One side of a power supply ( 27 ) is connected to the external power supply connecting terminal part ( 2 ), and another side of the power supply ( 27 ) is connected to the container ( 5 ) for energization. An electrostatic capacity between the water-level detecting electrode part ( 3 ) and the container ( 5 ) is measured by using the insulating coating ( 6 ) formed on the surface of the water-level detecting electrode part ( 3 ) as a dielectric. The water-level of water to be brought into contact with the water-level detecting electrode part ( 3 ) in the container ( 5 ) can be detected from the electrostatic capacity. Proportional target water-level in the boiler ( 7 ) is set based on at least one of the burning capacity, vapor pressure, supply water temperature, and electrical conductivity of boiler water, and at least one of the burning capacity, vapor pressure, supply water temperature, and electrical conductivity of boiler water during operation of the boiler ( 7 ) is detected. A difference between the proportional target water-level to be specified by the detected values and actual water-level in the boiler ( 7 ) detected by the electrode rod for detecting water-level ( 1 ) is constantly calculated.

The invention belongs to the technical field of chemical analysis or environment monitoring and provides a preparation method of a sensor for heavy metal ions Cd2+, Pb2+ and Cu2+ built based on alginic acid functionalized grapheme and a detection method of the heavy metal ions in a water body. The preparation method and the detection method have the benefits that by the utilization of carboxyl richly contained in alginic acid and a hydroxyl functional group, the heavy metal ions can be better absorbed, and in combination with the large specific surface area and the excellent electrical conductivity of the graphene, a sensing signal is enhanced, and the sensitivity is improved; according to potential difference, the different heavy metal ions Cd2+, Pb2+ and Cu2+ can be effectively distinguished; the detection method is used for the detection of the heavy metal ions Cd2+, Pb2+ and Cu2+, and the linearity ranges are 0.1-100 <mu>g/L, 0.5-100 <mu>g/L and 0.2-100 <mu>g/L respectively; the limits of detection are 0.021 <mu>g/L, 0.10 <mu>g/L, and 0.041 <mu>g/L respectively; the detection method has an important use value in the quick, sensitive and selective detection of heavy metals.

The invention discloses a device and a method for measuring the heat conductivity coefficient reduction rate of concrete in a uniaxial compression process. A concrete test sample is put into a bracket to be subjected to a compression load, and meanwhile a heating unit and a refrigerating unit establish a temperature difference between two planes of the concrete test sample; the bracket is used for fixing relative positions of the concrete test sample with the heating unit, the refrigerating unit, a heat insulating material and heat conduction silica gel; the concrete test sample is deformed under pressure, and extrudes the heat insulating material, the heat conduction silica gel, the refrigerating unit and the heating unit in order that the heat insulating material, the heat conduction silica gel, the refrigerating unit and the heating unit move outwards towards the periphery; peripheral support posts of the bracket are used for determining moving tracks of peripheral materials; spring pressing plates and springs on the support posts provide a proper peripheral pressure not influencing mechanics experiments in order to ensure that the refrigerating unit and the heating unit fit the surface of the concrete test sample, thereby reducing a contact thermal resistance as much as possible. Under the situation that the concrete test sample is under a certain compression load, a thermal flow density inside the concrete test sample reaches a steady state, and the temperature is distributed stably in a one-dimensional form in the concrete test sample.

The invention discloses a method for purifying silicon carbide micro powder for linear cutting. The method comprises the following steps of: removing carbon and oil after loading, making foaming experiments, and judging qualification if the surface has no oil; washing the material by using alkali, checking the pH (8.5 to 9.5) of a water sample, and judging qualification if the conductivity value is equivalent to the used water (the difference is less than or equal to 0.003ms/cm); and then adjusting the acidity, washing the material by excessive acid, checking the pH (6 to 7) of the water sample, judging qualification if the conductivity value is equivalent to the used water (the difference is less than or equal to 0.002ms/cm), and drying the material to obtain the purified qualified silicon carbide micro powder. The production process for the silicon carbide micro powder has the advantages of improving the SiC purity by carbon and oil removal, acid washing and alkali washing and reducing the content of impurities. The process has simple operation, short period and high efficiency.

The invention relates to a production method of an oil deposit, in particular to an oil deposit development production optimization method and system based on a connectivity method. The method comprises the steps that saturation calculation is conducted by taking inter-shaft communication units as objects to establish a precise front edge tracking method to obtain oil-water dual-phase production dynamics of each layer at shafts; information of inter-shaft conductivity, flow splitting, water injection efficiency and the like is obtained by inverting connectivity model parameters though automatically fitting oil deposit historical dynamics, and the information is taken as the basis to perform layered dynamic production allocation and injection allocation automatic optimizing design on the oil deposit through iterative computation to reduce low-efficiency water drive direction flow and improve injection-exploitation conflict. Application examples show that the method can perform rapid computation, accurate saturation tracking and production dynamics computation, an obtained layered water injection scheme can well achieve a water reducing and oil increasing effect, 50,000 cubic metersof predicted oil increasing after actual optimization of the oil deposit is conducted is achieved, and a novel idea for performing real-time optimization on an oil field injection-exploitation schemeis provided.