223 results about "Resistivity distribution" patented technology

The invention discloses a ground electromagnetic prospecting method based on an SPSP (Spread Spectrum) coding technology and a detection system thereof. The ground electromagnetic prospecting method based on the SPSP coding technology comprises the following steps of: supplying a current signal hopping according to a certain coded sequence to underground by a sending electrode, and using the current signal as a manual excitation source; receiving an electromagnetic field response message by a receiver, and meanwhile, synchronously recording the sent current signal and the geoelectrical response message of the position where the receiver is located by the receiver; and obtaining ground system response comprising the geoelectrical resistivity through a correlated identification method, and finally obtaining the distribution characteristics of the geoelectrical resistivity. According to the detection system applying the ground electromagnetic prospecting method disclosed by the invention, a sine-wave or square-wave signal in unipolarity or bipolarity in the whole preset frequency range can be sent by a transmitter, a sending sequence can hop according to a preset frequency pattern, and uncorrelated noise can be removed through a correlated identification detection method.

The present invention discloses electric impedance tomographic imaging method and apparatus for imaging nursing beside sickbed. The integral computerized data collecting system and the re-construction algorithm provides the interface and controls the imaging nursing process. The apparatus includes one computer and one connected data collecting system, the computer is equipped with program for controlling the data collecting system and algorithm for re-constructing image, and the data collecting system has also control module to apply excitation current to body signal collecting electrodes. The present invention features the several pairs of electrodes for applying excitation current and collecting body signals, the data collecting system providing constant AC excitation, high precision signal detection and programmed driving and measuring mode, and the calculation of body resistivity distribution and image display.

A method for detecting formation resistivity outside of metal casing using time-domain electromagnetic pulse in a borehole, the method including steps of a) providing a borehole large power pulse transmitting source, recording an induced electromotive force ε, and full time digital recording a transmitted waveform and a received signal; b) conducting transmission-reception and superimposing received signals to improve signal to noise ratio; c) calculating corresponding casing response according to known casing parameters and recorded current waveform of the transmitting source to obtain a relative induced electromotive force Δε_f; d) correcting relative induced electromotive force value; e) carrying out one-dimensional inversion and converting the observation signal into radial variation information of the formation resistivity; f) obtaining a two-dimensional image of the longitudinal and radial resistivity distribution of outer cased formation resistivity for measured well sections; and g) determining residual oil distribution in a reservoir from outer cased reservoir resistivity distribution.

The invention discloses a method for preparing vacuum zone melting high resistant silicon single crystal, comprising the two sequential major processes: polysilicon purification and crystal forming of silicon single crystal, wherein, the process of polysilicon purification comprises the steps of cleaning fire, charging, evacuating, preheating, melting materials heat sealing, growing narrow necks, shouldering, shoulder circuiting, equating diameter, ending and repeating; the process of crystal forming of silicon single crystal comprises the steps of cleaning fire, charging, evacuating, preheating, processing of chemicals, crystal seeding, shouldering, shoulder circuiting, equating diameter, ending and blowing out. With the method of the invention adopted to prepare silicon single crystal, electric resistivity, ultra-high purity, resistivity profile, uniformity of cross-section electric resistivity and minority carrier lifetime are greatly improved; purity of the silicon single crystal is above 11N, electric resistivity reaches 8000 omega/cm-30000omega/cm, uniformity of cross-section electric resistivity is less than 15%, and minority carrier lifetime is more than 600-1000Mus, thus greatly improving performance, stability and safety of the devices while realizing mass production of vacuum zone melting high resistant silicon single crystal.

An electrochromic device is provided. The device includes a substrate and an electrochromic stack on the substrate. The stack includes a first set of bus bars, a first transparent conductive layer, at least one electrochromic layer, a second transparent conductive layer, and a second set of bus bars, wherein at least one of the first transparent conductive layer or the second transparent conductive layer includes resistivity that varies by horizontal location according to a resistivity profile. In some embodiments the resistivity profile has a vertical component that may or may not be in addition to the horizontal component. Various embodiments of these materials can be tuned as to profiles of vertical resistance and horizontal sheet resistance.

This invention relates to a method and apparatus for concrete damage detection based on impedance imaging, which comprises the following steps: (1) setting multiple electrodes on target; (2) connecting the excitation input ports of former electrodes to the multi-way input switch; (3) forcing the drive sine current to every two electrodes by turns, measuring the current amplitudes and phases; (4) computing resistance distribution in the concrete; (5) acquiring and storing computation data to compare with given data for analysis.

The invention provides a crystalline silicon preparation method.The crystalline silicon preparation method includes that polycrystalline silicon and a dopant are added into a crucible of a crystalline silicon ingot furnace or a single crystal furnace; in presence of protective gas, the polycrystalline silicon and the dopant are heated to melt completely to form silicon melts, crystalline silicon growth parameters are adjusted to enable the silicon melts to start to grow crystals, and in a crystal growing process, when resistivity of the crystals reaches clinical resistivity, new silicon melts formed by the polycrystalline silicon are replenished into residual silicon melts in the crucible to enable the resistivity of the crystals to be adjusted to target resistivity, and the new silicon melts continue growing crystals so as to obtain crystalline silicon with target yield after crystallization of the silicon melts in the crucible is completed.The crystalline silicon preparation method is capable of solving the problems of too many low-resistivity regions, scattered resistivity distribution and low crystalline silicon yield in the prior art.The invention further provides the crystalline silicon.

The invention relates to a method for calculating apparent formation water resistivity spectrum and parameters by applying electric imaging data of point-by-point calibration. The point-by-point calibration comprises the following steps: using a logging data editing tool to lead the electric imaging data to be consistent with the shallow resistivity depth; calculating the average current value of images of the electric imaging data; for each image frame, calculating a calibration coefficient by a conductivity value corresponding to the shallow resistivity value at the same depth point; carrying out calculation of the apparent formation water resistivity spectrum by applying the electric imaging data; according to the fact that the electric imaging of the shallow resistivity calibration is substantially a conductivity image of a well-wall flushed zone, defining the apparent formation water resistivity of one pixel point of the electric imaging data; calculating the apparent formation water resistivity spectrum parameters by applying the electric imaging data; introducing the average value to express the deviation degree of a main peak from a base line in the apparent formation water resistivity spectrum; using variance to express the width of the apparent formation water resistivity distribution spectrum; carrying out point-by-point calibration on the electric imaging data by applying shallow resistivity, calculating the apparent formation water resistivity spectrum of the electric imaging data, wherein the extracted average value and extracted variance of the apparent formation water resistivity spectrum have obvious application effect on evaluating the performance of reservoir fluid.

The invention discloses a polysilicon ingot furnace capable of uniformly distributing the resistivity of ingots. The gas outlet of a gas inlet pipe of the polysilicon ingot furnace is extended to a position close to the inner wall of a crucible, the included angle between the central axis of gas flow ejected from the gas outlet and the central axis of the crucible is 20-30 degrees, when being ejected from the gas outlet of the gas inlet pipe, argon is ejected to the surface of silicon liquid obliquely downwards, the original direct blowing manner is changed into an oblique blowing manner, and the central axis of gas flow ejected from the gas outlet and the central axis of the crucible are skew lines, so that the gas flow ejected obliquely downwards can drive the silicon liquid in the crucible to rotate to fully disperse impurities contained in the silicon liquid in a silicon solution to uniformly distribute the liquid phase components so as to avoid the existence of impurity enrichment regions in the ingots and ensure the uniform distribution of the resistivity of the ingots, and the silicon liquid in the crucible is stirred to promote the volatilizable impurities contained in the silicon liquid to be volatilized as soon as possible. The polysilicon ingot furnace is suitable for popularization and application in the field of polysilicon production equipment.

A method of determining electric resistivity of an earth formation (1) surrounding a wellbore filled with a wellbore fluid, is provided, which method comprises: operating a resistivity logging tool (2) in the wellbore so as to provide a plurality of resistivity logs (FLG1, . . . , n) (3) of the earth formation (1) for different radial intervals (1, . . . , n) relative to the wellbore; for each radial interval (k), selecting a modelled resistivity profile (Rmodk) (4); inputting the modelled resistivity profiles (Rmod1, . . . , n) (4) to a logging tool simulator (6) so as to provide for each radial interval (k) a modelled resistivity log (MLGk) (7) having a depth of investigation corresponding to the radial interval (k); for each radial interval (k) updating the modelled resistivity profile (Rmodk) (7) in dependence of an observed deviation of the resistivity log (FLGk) (3) from the modelled resistivity log (MLGk) (7); and repeating steps c)-d) until for each radial interval (k) the difference between the resistivity log (FLGk) (3) and the corresponding modelled resistivity log (MLGk) (7) is below a selected threshold value (8).

A group III nitride semiconductor crystal substrate has a diameter of at least 25 mm and not more than 160 mm. The resistivity of the group III nitride semiconductor crystal substrate is at least 1×10⁻⁴ Ω·m and not more than 0.1 Ω·cm. The resistivity distribution in the diameter direction of the group III nitride semiconductor crystal is at least −30% and not more than 30%. The resistivity distribution in the thickness direction of the group III nitride semiconductor crystal is at least −16% and not more than 16%.

The invention belongs to the technical field of geophysical exploration and relates to a hardware composition proposal of a three-dimensional resistivity imaging system. The invention comprises a hardware composition proposal applied in the scientific research application and a hardware composition proposal applied to engineering application; under the control of a notebook computer, a control command, a state data and a measurement data are transmitted by a mixed network composing of a CAN bus and a RS485 bus; an electrode switching device is adopted to select the communication of a power supply anode (A), a power supply cathode (B), a measurement common electrode (N), a measurement collecting electrode (M) and a polarization electrode or non-polarization electrode; a data collecting sub-station device carries out data collecting and data pre-processing; the pre-processed data is transmitted to the notebook computer for memory, analysis and calculation; and the resistivity distribution image is imaged and displayed at the measurement region.

The invention discloses a computer method for realizing an auricular point pseudo-color distribution graph and the method is characterized by comprising the following steps: initializing in the computer and inputting a system auricular point graph; setting a signal detecting module which consists of a test interface sub-module, a measuring control sub-module and a result analysis sub-module; carrying out pseudo-color mapping according to auricular point resistivity and giving colors to the region except the auricular points by an interpolation method, and carrying out image processing to obtain the auricular point pseudo-color distribution map with an auricle contour and partition information. Then, acupoints are measured according to standard steps. By adopting the method, the auricular point resistivity can be visually displayed in the pseudo-color form, and an auricle pseudo-color resistivity distribution graph can be drawn, thus being convenient for positioning a lesion region, and simultaneously, three measuring modes which are overall measurement, partial measurement and random measurement can be adopted according to actual requirements, thus improving the adaptation range of the auricular point detection.

The invention discloses a safety monitoring method for an internal diaphragm of a lithium-ion power battery. The safety monitoring method comprises the following steps: testing the internal apparent resistivity of the lithium-ion power battery to obtain the internal resistivity distribution of the lithium-ion power battery; determining an internal temperature field according to the internal resistivity distribution of the lithium-ion power battery and tracking a high temperature variation region; obtaining the change of the stretching quantity of the diaphragm at different temperatures inside the lithium-ion power battery and determining the relation between the internal temperatures and the stretching quantity; determining the stretching quantity of the diaphragm and assessing the internal performance condition of the lithium-ion power battery according to the stretching quantity; locating the damage of the diaphragm and predicting the deformation degree of the diaphragm. The safety monitoring method for the internal diaphragm of the lithium-ion power battery has the advantages that the damage condition of the internal diaphragm is deduced according to the change of the internal apparent resistivity of the lithium-ion power battery, the thermal loss location and the deformation degree prediction on the internal diaphragm of the lithium-ion power battery in a high temperature environment are realized, and the technical bottleneck of the safety monitoring mode of a traditional battery is broken through; besides, the safety monitoring method plays a directing role in research in the fields of life prediction and load control of the lithium-ion power batteries, and new energy resources.

A downhole drilling tool is adapted to be placed in a borehole formed in the earth. The downhole drilling tool has mounted thereto at least one of a transmitter for generating and a receiver for sensing at least one component of an electromagnetic field within a distant earth region. The tool also has a device configured to acquire subsurface data from the at least one component of the electromagnetic field; and a device configured to calculate a resistivity distribution of the distant earth region from the subsurface data. A geophysical survey is performed with a downhole drilling tool by transmitting at least one component of an electromagnetic field through the distant earth region; acquiring subsurface data from the at least one component of the electromagnetic field; and calculating a resistivity distribution of the distant earth region from the subsurface data.

The invention discloses a diameter transitional czochralski silicon growing method. The method comprises the following steps of: A, setting a required transitional single crystal diameter and an initial diameter transitional single crystal equal diameter length L according to the axial resistance distribution condition from the head to the tail of a crystal bar; B, carrying out normal czochralski silicon production including steps of melting, temperature stabilizing, guiding the crystal, shouldering, shoulder rotating and the like; C, setting the diameter transitional size and the diameter transitional length according to step A, carrying out a first equal diameter growing step, and when the single crystal equal diameter of the first equal diameter growing step grows to the designated length L, starting the diameter transition; D, after the diameter of the single crystal is turned into the required diameter, carrying out the next equal diameter growing step; and E, completing a closing process after the length of a silicon single crystal bar meets a production requirement.

The invention discloses a system and a method for testing the mechanical-electrical coupling effect of an electrical conducting functional material . The system comprises an electrical conducting functional material sample, a sample electrode, an insulation tape, an external wire on the electrode, a sample clamping device, a displacement sensor, a transmission shaft, a driving motor, a force sensor, a handheld four-point probe, a digital source meter B, a digital source meter A and a DC power supply, wherein an integral load-displacement curve can be obtained through accurate control of parameters such as voltage strength, conduction time and loading speed; mechanical and electrical properties such as elasticity modulus, tensile strength, elongation at break, yield strength, integral volume resistivity and micro-area volume resistivity distribution of a material under the action of different force fields and electric fields can be obtained through further calculation. Therefore, measurement and analysis of the mechanical-electrical coupling effect of the electrical conducting functional material can be realized accurately and reliably, and the system and the method are suitable for electrical conducting functional materials such as conductive macromolecule, piezoceramics, a polymer-matrix composite, a ceramics-matrix composite, and a metal-matrix composite.

A device and method for producing Ga doped silicone single crystal with a diameter between 150 and 165 mm and a narrow resistivity distribution range (from 3 Ω·cm to 0.5 Ω·cm). The device is characterized by the use of a shorter heater and a funnel shaped gas flow guide capable of blowing an inert gas such as Ar straight to the crystallization frontier at the interface between outer surface of the nascent single crystal ingot and the surface of the melt of polycrystalline silicone raw materials in a quartz crucible.

The invention discloses an interface pressure distribution testing sensing element. The interface pressure distribution testing sensing element comprises a sensing film, electrodes uniformly arranged around the sensing film at intervals, a lead connected with the electrodes and an upper and lower insulating paint layer. The sensing film is made from a conductive polymer composite material provided with a piezo-resistive sensitivity characteristic, and the electrodes and the lead are used for outputting resistivity information of the sensing film in different positions. When in testing, the lead is connected with a testing instrument, the electrical impedance imaging technology is used for acquiring, testing and computing so as to obtain the resistivity distribution of the sensing film in different positions, and then the pressure distribution can be obtained through the relationship between the sensing film pressure and the resistivity. The interface pressure distribution testing sensing element can be used for measuring the interface pressure distribution and change, and has the advantages of simple structure, ultra-thin film, strong flexibility, high resolution and precision, large measuring range and low cost.