Method and system for testing performance of copper oxide high-temperature superconductor

Abstract

The invention discloses a method and system for testing the performance of a copper oxide high-temperature superconductor, and belongs to the technical field of intelligent sensing systems, and the method comprises the steps: obtaining an original resistance-temperature change curve and a plurality of measurement resistance-temperature change curves of the copper oxide high-temperature superconductor; marking an attenuation initial temperature and a superconducting initial temperature in the resistance-temperature change curve to obtain a minimum temperature deviation of the attenuation initial temperature; screening an attenuation initial change trend section; acquiring an attenuation change steep coefficient to obtain a corrected temperature deviation of the attenuation initial temperature; obtaining an attenuation initial temperature interval and a trend influence factor of each measurement temperature in the attenuation initial temperature interval; obtaining an adjustment weight of each measurement temperature, and obtaining an adjusted attenuation initial temperature; obtaining the adjusted superconducting initial temperature; the critical temperature is obtained, and the performance test of the copper oxide high-temperature superconductor is achieved. According to the invention, the critical temperature of the copper oxide high-temperature superconductor can be tested and determined more accurately and stably.

Description

Technical Field

[0001] This invention relates to the field of intelligent sensing system technology, specifically to a method and system for testing the performance of copper oxide high-temperature superconductors. Background Technology

[0002] Copper oxide high-temperature superconductors are among the earliest discovered and most widely studied unconventional superconducting materials, exhibiting high critical temperatures under ambient pressure. Therefore, it has long been one of the important objects of research and application development of high-temperature superconductivity. Superconducting materials can exhibit near-zero resistance and perfect diamagnetism below their critical temperature, making them of great potential application value in fields such as power transmission and power equipment, high-field magnets and magnetic resonance imaging, magnetic levitation and high-speed transportation, precision sensing and electromagnetic shielding.

[0003] In the process of studying the relationship between electronic nematic order and superconductivity, the critical temperature was accurately determined. This is a crucial testing step. Critical temperature. This temperature range can be used to define the transition temperature range between the superconducting and normal states, providing a temperature benchmark for analyzing related physical properties near the superconducting transition. It also affects the effectiveness of comparing experimental data between different doped systems or samples. Currently, the mainstream method for performance testing of copper oxide high-temperature superconductors is the resistance measurement method: by programmably cooling the material, the change in its resistance with temperature is simultaneously measured to obtain a resistance-temperature curve. In this curve, the temperature at which the resistance begins to decrease significantly (called the initial decay temperature) is typically used as the reference point. The temperature at which resistance drops sharply to zero (called the superconducting initial temperature) is called the superconducting initial temperature. The critical temperature of a material is ultimately determined through calculation or empirical definition. This method is a general means of characterizing the superconducting transition and dividing the temperature range between the superconducting state and the normal state.

[0004] However, the aforementioned resistance measurement method still suffers from insufficient accuracy and repeatability in determining the critical temperature. Due to factors such as material micro-inhomogeneity, measurement noise, and thermal fluctuations, the initial temperature decreases during multiple measurements or comparisons with different samples. With the initial temperature of superconductivity Small, random fluctuations will occur in all of them, leading to a decrease in the critical temperature. The unstable values ​​reduce its accuracy and repeatability. This instability further affects the performance based on the critical temperature. This undermines the reliability of the analysis of behavior near the superconducting transition and weakens the effectiveness of data comparison between different doped systems or different samples. Summary of the Invention

[0005] The technical problem to be solved by this invention is to provide a method and system for testing the performance of copper oxide high-temperature superconductors, aiming to more accurately and stably test and determine the critical temperature of copper oxide high-temperature superconductors. This study solves the technical problem of inaccurate and unstable determination of critical temperature caused by noise interference, data jumps, and measurement system errors in existing measurements. It provides more stable and comparable key experimental data support for studying the correlation between electron nematic order and superconductivity, exploring its particle-hole asymmetry characteristics and microscopic mechanisms in this field.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0007] A method for testing the performance of copper oxide high-temperature superconductors includes the following steps:

[0008] The original resistance of the copper oxide high-temperature superconductor was obtained, and the measured resistance was obtained by adjusting the measurement temperature. The original resistance-temperature change curve and several measured resistance-temperature change curves were obtained.

[0009] The initial decay temperature and the initial superconducting temperature are marked in the resistance-temperature change curve. Based on the slope changes of adjacent data points of the initial decay temperature in the original resistance-temperature change curve, the minimum temperature deviation of the initial decay temperature is obtained in combination with the original resistance. The differences in the slope changes of adjacent data points in the measured resistance-temperature change curve are analyzed, and the initial decay trend segment is selected. According to the distribution of the upper and lower limits of the initial decay trend segment in each measured resistance-temperature change curve among all initial decay trend segments, the decay steepness coefficient is obtained, and then the corrected temperature deviation of the initial decay temperature is obtained.

[0010] Based on the initial decay temperature and its corrected temperature deviation in the original resistance-temperature change curve, the initial decay temperature range is obtained, and the trend changes of the measured temperatures before and after removal are compared to obtain the trend influence factor of each measured temperature. The decimal fluctuation of the measured resistance in different resistance-temperature change curves is analyzed to obtain the adjustment weight of each measured temperature. The initial decay temperature range is weighted to obtain the adjusted initial decay temperature. The adjusted initial superconducting temperature is then obtained.

[0011] Based on the adjusted initial decay temperature and the adjusted initial superconducting temperature, the critical temperature is obtained, enabling performance testing of copper oxide high-temperature superconductors.

[0012] A further improvement to the technical solution of the present invention is that the specific method for obtaining the minimum temperature deviation of the initial attenuation temperature is as follows:

[0013] Obtain the range of a digital voltmeter and the range of the current source. ,Will and The ratio of the minimum resistance deviation to the minimum resistance deviation is used as the minimum resistance deviation. The curve segment corresponding to the original resistance to the original resistance of the transition ratio in the original resistance-temperature change curve is used as the resistance transition zone. The slope of each data point in the resistance transition zone is calculated, and the average of the slopes of all data points is used as the resistance temperature coefficient of the transition zone. The ratio of the minimum resistance deviation to the resistance temperature coefficient of the transition zone is used as the minimum temperature deviation of the initial temperature decay.

[0014] A further improvement to the technical solution of this invention lies in the following: the specific method for obtaining the initial attenuation trend segment is as follows:

[0015] For any resistance-temperature change curve, obtain the slope of all data points of the resistance-temperature change curve, preset the abrupt change ratio, and use the product of the abrupt change ratio and the mean of the slope of all data points of the resistance-temperature change curve as the abrupt change threshold of the resistance-temperature change curve.

[0016] Obtain the absolute value of the difference in slope between adjacent data points. If the absolute value of the difference in slope is greater than the abrupt change threshold, take the data point corresponding to the minimum temperature among two adjacent data points as a segment point, obtain all segment points of the measured resistance-temperature change curve, obtain several trend segments of the measured resistance-temperature change curve based on the segment points, and take the trend segment where the initial temperature of the measured resistance-temperature change curve is located as the initial change trend segment of the measured resistance-temperature change curve.

[0017] A further improvement to the technical solution of the present invention is that the specific method for obtaining the attenuation steepness coefficient is as follows:

[0018] Obtain the upper and lower temperature limits of the initial decay trend segment of any measured resistance-temperature change curve, and denote the closed interval formed by the lower and upper temperature limits as the initial decay temperature interval of the measured resistance-temperature change curve.

[0019] Obtain the initial decay trend segment, upper and lower temperature limits, and initial decay temperature range for each resistance-temperature curve. For the upper temperature limit of the initial decay trend segment of any resistance-temperature curve, use the ratio of the number of times this upper temperature limit appears in all initial decay temperature ranges of resistance-temperature curves to the number of resistance-temperature curves as the reference weight for this upper temperature limit. Then, weight and average the upper temperatures of the initial decay trend segments of all resistance-temperature curves according to their respective reference weights, and use the result as the upper temperature limit for decay.

[0020] Obtain the lower limit of the decay change temperature, and use the reciprocal of the difference between the upper limit of the decay change temperature and the lower limit of the decay change temperature as the decay change steepness coefficient.

[0021] A further improvement to the technical solution of this invention lies in the following: the specific method for obtaining the corrected temperature deviation of the initial attenuation temperature is as follows:

[0022] The sum of 1 and the aforementioned attenuation steepness coefficient, multiplied by the minimum temperature deviation of the initial attenuation temperature, is used as the corrected temperature deviation of the initial attenuation temperature.

[0023] A further improvement to the technical solution of the present invention is that the specific method for obtaining the initial attenuation temperature range is as follows:

[0024] The range obtained by adding or subtracting the corrected temperature deviation from the initial temperature attenuation in the original resistance-temperature change curve is taken as the initial temperature attenuation range.

[0025] A further improvement to the technical solution of this invention lies in the following: the specific method for obtaining the trend influence factors of each measured temperature is as follows:

[0026] The original resistance-temperature change curve is truncated by the initial temperature range of attenuation to obtain a segment of the curve, which is then used as the attenuation cutoff resistance-temperature change curve. A vertical baseline is constructed using the upper temperature limit of the attenuation cutoff resistance-temperature change curve, and a horizontal baseline is constructed using the minimum resistance value, thus obtaining the original area of ​​the attenuation cutoff resistance-temperature change curve.

[0027] For any measurement temperature within the initial attenuation temperature range, remove the data point corresponding to that measurement temperature, refit the original resistance-temperature change curve based on other data points, and truncate it using the initial attenuation temperature range. The resulting curve segment is used as the truncated resistance-temperature change curve for that measurement temperature. Obtain the area of ​​the truncated resistance-temperature change curve and use it as the truncated area for that measurement temperature. The absolute value of the difference between the original area and the truncated area for that measurement temperature is used as the trend influence factor for that measurement temperature.

[0028] A further improvement to the technical solution of this invention lies in the following: the specific method for obtaining the adjustment weights of each measured temperature and weighting the initial attenuation temperature range to obtain the adjusted initial attenuation temperature is as follows:

[0029] For any identical measurement temperature in different resistance-temperature change curves, obtain the measurement resistance corresponding to that measurement temperature in different resistance-temperature change curves, and use it as several measurement resistances for that measurement temperature. Then, split all measurement resistances into integer and fractional parts, and use the fractional part of each measurement resistance corresponding to the mode of the integer parts of all measurement resistances as the set of fractional parts for that measurement temperature.

[0030] Obtain the variance of all decimal data in the set of decimal places of the measured temperature, and use it as the resistance fluctuation coefficient of the measured temperature. Multiply the sum of 1 and the resistance fluctuation coefficient by the trend influence factor of the measured temperature, and use it as the trend influence coefficient of the measured temperature.

[0031] Obtain the trend influence coefficient of each measured temperature in the initial temperature range of decay, normalize the weight of all trend influence coefficients, and use the result as the adjustment weight of each measured temperature.

[0032] For each measured temperature in the initial decay temperature range, a weighted sum is calculated based on their respective adjustment weights, and the result is used as the adjusted initial decay temperature.

[0033] A further improvement to the technical solution of this invention lies in the following: the adjusted initial superconducting temperature is obtained using the following method:

[0034] A proximity ratio is preset, and the curve segment from the original resistance to zero resistance in the original resistance-temperature change curve is taken as the resistance proximity region. The slope of each data point in the resistance proximity region is calculated, and the average slope is taken as the resistance temperature coefficient of the proximity region. Then, the ratio of the minimum resistance deviation to the resistance temperature coefficient of the proximity region is taken as the minimum temperature deviation of the superconducting initial temperature.

[0035] For any measured resistance-temperature change curve, the trend segment where the superconducting initial temperature is located in the measured resistance-temperature change curve is taken as the superconducting initial change trend segment of the measured resistance-temperature change curve. The upper and lower limits of the superconducting change temperature are obtained from this, and then the superconducting change steepness coefficient is obtained. This coefficient is used to correct the minimum temperature deviation of the superconducting initial temperature, and the corrected temperature deviation of the superconducting initial temperature is obtained.

[0036] Based on the corrected temperature deviation of the superconducting initial temperature, the superconducting initial temperature range is obtained, and the superconducting cutoff resistance-temperature change curve is obtained from it. Then, the trend influence factor of each measured temperature is obtained. The decimal set of each measured temperature is obtained, the trend influence coefficient of each measured temperature is obtained, and then the adjustment weight of each measured temperature is obtained. The weighted average is then used to obtain the adjusted superconducting initial temperature.

[0037] A copper oxide high-temperature superconductor performance testing system includes a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor executes the computer program to implement the steps of the above-described method.

[0038] The technological advancements achieved by this invention due to the adoption of the above technical solutions are as follows:

[0039] 1. Critical temperature caused by the dispersion of resistance-temperature data, temperature hysteresis, and resolution limitations of measuring instruments. To address the fluctuation problem, this invention significantly reduces the impact of random errors in single measurements and the subjectivity of reading points by calculating the minimum temperature deviation under instrument accuracy constraints, adaptive deviation modification based on the transition steepness coefficient, and weighted temperature range analysis. This makes the critical temperature under multiple measurements more stable. The determination results are more consistent and reliable.

[0040] 2. This invention utilizes the range of a voltmeter and a current source to directly calculate the minimum resistance deviation and convert it into the minimum temperature deviation, thus matching the temperature range construction with the actual accuracy of the measuring equipment. By extracting trend segments and calculating steepness coefficients, the temperature deviation is dynamically corrected, allowing the allowable deviation range to be adaptively adjusted according to the steepness of the transition zone, thereby enhancing the robustness of the testing method to different samples and noisy environments.

[0041] 3. This invention quantifies the influence of each temperature point on the overall curve shape by removing individual points, refitting the curve, and calculating the area difference; it characterizes the measurement discreteness at that location based on the fluctuation (e.g., variance) of the resistance value at the same temperature point in multiple measurements; and it combines the above two factors to form an adjustment weight, performing a weighted summation on the temperature range to determine the final initial attenuation temperature. With the initial temperature of superconductivity It more accurately reflects the physical trends and statistical characteristics of resistance transitions.

[0042] 4. This invention addresses the initial temperature of attenuation. With the initial temperature of superconductivity By analyzing the resistance temperature coefficients of the transition region and the adjacent region separately, the estimated temperature deviation more accurately reflects the resistance change behavior at each stage, thus improving the overall critical temperature. The physical rationality of the calculation.

[0043] 5. This invention does not rely on idealized mathematical assumptions, but closely integrates actual measurement procedures, instrument conditions and data fluctuation characteristics to form a complete processing flow from data acquisition and error analysis to weighted output. It is easy to implement in existing testing systems and helps to improve the efficiency and reliability of copper oxide high-temperature superconductor performance testing in laboratories and industrial production.

[0044] 6. This invention provides a more accurate and stable critical temperature. The testing methods help to more accurately characterize the superconducting properties of materials, providing reliable data support for optimizing material synthesis processes, evaluating batch consistency, and studying related mechanisms. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0046] Figure 1 This is a schematic diagram of a copper oxide high-temperature superconductor performance testing method provided in an embodiment of the present invention;

[0047] Figure 2 This is a schematic diagram of the resistance-temperature change curves (including the original resistance-temperature change curve and multiple measured resistance-temperature change curves) provided in the embodiments of the present invention.

[0048] Figure 3 This is a transformation region analysis diagram provided in an embodiment of the present invention;

[0049] Figure 4 The initial attenuation temperature provided in the embodiments of the present invention Analysis chart;

[0050] Figure 5 The superconducting initial temperature provided in the embodiments of the present invention Analysis chart;

[0051] Figure 6 This is a schematic diagram of the distribution of multiple measurement curves in an embodiment of the present invention;

[0052] Figure 7 The final critical temperature in the embodiments of the present invention Schematic diagram. Detailed Implementation

[0053] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0054] like Figure 1 As shown, a method for testing the performance of copper oxide high-temperature superconductors includes the following steps:

[0055] Step S001: Obtain the original resistance of the copper oxide high-temperature superconductor, and obtain the measured resistance by adjusting the measurement temperature, thus obtaining the original resistance-temperature change curve and several measured resistance-temperature change curves; such as... Figure 2 As shown.

[0056] The purpose of this embodiment is to obtain the critical temperature of the copper oxide high-temperature superconductor, and then to conduct performance tests on the copper oxide high-temperature superconductor based on the critical temperature. This first requires laboratory measurements and multiple measurements to obtain the original resistance-temperature curve and multiple measured resistance-temperature curves. Due to the discreteness of the resistance-temperature data, temperature hysteresis, and the resolution limitations of the measuring instruments, the initial temperature decays. With the initial temperature of superconductivity In multiple measurements, the temperature typically fluctuates within a small range rather than at a single point. Directly using readings from a single curve or simple averaging can easily lead to a critical temperature reading. Determined to be unstable.

[0057] Specifically, resistance is measured using a Wheatstone bridge or the voltmeter-ammeter method, and the four-terminal connection method is used to eliminate errors in wiring resistance and contact resistance. The standard resistor used in the measurement circuit has a resistance value of [value missing]. Its voltage value is The voltage value of the tested copper oxide high-temperature superconductor is The resistance value of the tested copper oxide high-temperature superconductor is... , and serve as its original resistance.

[0058] Furthermore, the temperature change characteristics of metal or semiconductor resistance are utilized for measurement. Platinum resistance thermometers are used for temperature measurement, and the specific calculation formula is as follows: ,in This indicates the resistance value of the platinum resistance thermometer. and This was obtained through actual laboratory calibration. Alternatively, an existing platinum resistance temperature sensor can be used directly, which will not be elaborated upon in this embodiment. Laboratory measurements were performed according to the requirements of the national standard GB / T 31780-2015 "Critical Temperature Measurement: Resistance Method for Determining the Critical Temperature of Composite Superconductors" to obtain the laboratory-measured resistance-temperature curve. Then, the test sample was tested multiple times. The general process was as follows: the test sample was mounted entirely on an insulating substrate, and the test sample was mounted on a sample rod. The test sample was then removed or placed in liquid nitrogen. The sample rod contained a current line providing current, a potential line for measuring voltage, and a platinum resistance temperature sensor. The liquid nitrogen was placed in an experimental stainless steel vacuum Dewar container. After the liquid nitrogen settled, approximately 30 cm from the bottom of the container, an external DC digital voltmeter (e.g., PZ158, Keithley) was used. 2182), and a programmable current source is used to provide circuit current; as the temperature decreases, this embodiment records the corresponding temperature and voltage every 5 minutes, and uses the temperature as the measurement temperature; when the temperature drops to the initial decay temperature measured in the laboratory, it is measured every half minute (i.e., depending on the rate of change of resistance); when the resistance of the test sample is close to zero, the zero resistance temperature is obtained by using the voltage after the current is changed in the forward and reverse directions; in this way, the resistance-temperature change curve of the test is constructed, and the resistance obtained at each measurement temperature is used as the corresponding measurement resistance.

[0059] Furthermore, such as Figure 2 As shown, the resistance-temperature change curve measured in the laboratory is recorded as the original resistance-temperature change curve, where the vertical axis of the resistance-temperature change curve is resistance (Ω) and the horizontal axis is temperature (K). The resistance of the copper oxide high-temperature superconductor at room temperature is recorded as the original resistance. All resistance-temperature change curves obtained by testing (excluding the original resistance-temperature change curve) are recorded as the measured resistance-temperature change curves. All resistance-temperature change curves include several data points obtained by mapping the measured temperature to the measured resistance.

[0060] It should be noted that the resistance-temperature change curves are all obtained by fitting the measured temperature and the corresponding resistance through data points. Therefore, the slope of the data points in the subsequent curves is the slope of the data points corresponding to the measured temperature and the corresponding resistance. The slope of the data points is calculated by using the derivative of the fitted curve. The curve fitting of the data points is performed by least squares curve fitting, which is a well-known technique and will not be described in detail in this embodiment. All subsequent curve fittings are performed using the least squares method.

[0061] Step S002: Mark the initial decay temperature and the initial superconducting temperature in the resistance-temperature change curve. Based on the slope change of the data points near the initial decay temperature in the original resistance-temperature change curve, combine with the original resistance to obtain the minimum temperature deviation of the initial decay temperature.

[0062] Analyze the differences in slope changes between adjacent data points in the resistance-temperature change curves and select the initial attenuation trend segments. Based on the distribution of the upper and lower limits of the initial attenuation trend segments in each resistance-temperature change curve across all initial attenuation trend segments, obtain the attenuation steepness coefficient, and then obtain the corrected temperature deviation of the initial attenuation temperature.

[0063] It should be noted that the critical temperature is obtained based on the initial decay temperature and the initial superconductivity temperature. Therefore, it is first necessary to accurately obtain the initial decay temperature and the initial superconductivity temperature, which are usually range data. However, during multiple measurements of the tested copper oxide high-temperature superconductor, it is necessary to gradually refine the range to obtain the critical temperature. This requires first analyzing the relationship between resistance and temperature based on the original resistance-temperature curve, such as... Figure 3 As shown, considering the allowable deviation of the measurement range, the minimum resistance deviation and the minimum allowable temperature deviation are obtained.

[0064] Preferably, in one embodiment of the present invention, the initial decay temperature and the initial superconducting temperature are marked in the resistance-temperature change curve. Based on the slope change of the data points adjacent to the initial decay temperature in the original resistance-temperature change curve, the minimum temperature deviation of the initial decay temperature is obtained in combination with the original resistance. The specific method includes:

[0065] like Figure 4 , Figure 5 As shown, the temperature at which the resistance of the copper oxide high-temperature superconductor begins to decrease is marked as the initial decay temperature. The temperature at which the resistance of a copper oxide high-temperature superconductor drops to zero is marked as the initial superconducting temperature. The normal state and superconducting state of copper oxide high-temperature superconductors are distinguished based on the critical temperature, where the critical temperature is... This embodiment uses the attenuation initial temperature. With the initial temperature of superconductivity The mean is expressed as the average.

[0066] It should be further noted that, due to the effects of data dispersion and temperature hysteresis, the initial decay temperature and the initial superconducting temperature are actually ranges of minute variation, not precise single temperature points. Therefore, a weighted average is required to obtain the accurate initial decay temperature and the initial superconducting temperature, and thus the critical temperature. .

[0067] Obtain the measurement accuracy of a digital voltmeter and the measurement accuracy of the current source. ,Will and The ratio of is taken as the minimum resistance deviation and denoted as . The preset conversion ratio is described in this embodiment as 0.9. Implementers can set it according to the specific superconductor structure and performance, depending on the doping concentration and structure of the copper oxide high-temperature superconductor. This embodiment only describes the general method and does not provide specific details; subsequent other ratio thresholds are also described using the general method. The curve segment from the original resistance to the original resistance at the conversion ratio in the original resistance-temperature change curve is taken as the resistance conversion region, i.e., the curve segment from the data point corresponding to the original resistance at the initial decay temperature to the data point corresponding to 0.9 times the original resistance. The slope of each data point in the resistance conversion region is calculated, and the average of the slopes of all data points is taken as the resistance temperature coefficient of the conversion region. The ratio of the minimum resistance deviation to the resistance temperature coefficient of the conversion region is taken as the minimum temperature deviation at the initial decay temperature. .

[0068] It should be further noted that in measuring the resistance-temperature change curve, the trend changes in different segments of the curve are different, that is, the slope will change abruptly. Therefore, it is necessary to perform segmented analysis and extract the curve segment where the initial decay temperature is located to obtain the initial decay trend segment, so as to provide a basis for analyzing the allowable deviation of subsequent multiple measurements of the initial decay temperature.

[0069] Preferably, in one embodiment of the present invention, the method for analyzing the slope difference between adjacent data points in the resistance-temperature change curve and filtering out the initial attenuation trend segment is as follows:

[0070] For any resistance-temperature change curve, the slope of all data points on the curve is obtained, and a mutation ratio is preset. In this embodiment, the mutation ratio is described as 0.2. The implementer can set it according to the specific superconductor structure and performance. The product of the mutation ratio and the mean of the slopes of all data points on the resistance-temperature change curve is used as the mutation threshold of the curve. The absolute value of the difference in slope between adjacent data points is obtained. If the absolute value of the difference in slope is greater than the mutation threshold, the data point corresponding to the minimum temperature between two adjacent data points is taken as a segmentation point (the resistance-temperature change curve shows a decreasing trend). The data points are segmented based on the minimum temperature among adjacent data points (i.e., the last data point in the range of temperature from high to low and resistance from large to small). All segment points of the measured resistance-temperature change curve are obtained. Based on the segment points, several trend segments of the measured resistance-temperature change curve are obtained. The trend segment where the initial decay temperature of the measured resistance-temperature change curve is located is taken as the initial decay trend segment of the measured resistance-temperature change curve. It should be noted that the initial decay temperature in different measured resistance-temperature change curves may be different. The initial decay temperature and the initial superconducting temperature in each measured resistance-temperature change curve are marked in the curve.

[0071] It should be further explained that after obtaining the initial attenuation trend segment in a single measured resistance-temperature change curve, it is necessary to conduct a comprehensive analysis of the distribution of the upper and lower limits of the initial attenuation trend segments in all measured resistance-temperature change curves in order to quantify the allowable deviation of different degrees under multiple measurements. The upper and lower limits of the attenuation change temperature are obtained by using the frequency of occurrence as a reference weight and then by weighting.

[0072] Preferably, in one embodiment of the present invention, based on the distribution of the upper and lower limits of the temperature of the initial attenuation trend segment in each measured resistance-temperature change curve across all initial attenuation trend segments, the attenuation steepness coefficient is obtained, thereby obtaining the corrected temperature deviation of the initial attenuation temperature. The specific method includes:

[0073] Obtain the upper and lower temperature limits of the initial decay trend segment of any resistance-temperature change curve, and denote the closed interval formed by the lower and upper temperature limits as the initial decay temperature interval of the resistance-temperature change curve. Obtain the initial decay trend segment, its upper and lower temperature limits, and the initial decay temperature interval for each resistance-temperature change curve using the above method. For the upper temperature limit of any resistance-temperature change curve's initial decay trend segment, use the ratio of the number of times this upper temperature limit appears in all resistance-temperature change curves' initial decay temperature intervals (i.e., within the corresponding interval) to the number of resistance-temperature change curves as the reference weight for this upper temperature limit. Weight the upper temperatures of all resistance-temperature change curves' initial decay trend segments according to their respective reference weights, and take the result as the upper temperature limit of the decay change.

[0074] Furthermore, similarly, the lower limit of the initial decay trend segment of any measured resistance-temperature change curve is obtained, along with the ratio of the number of times it appears in the initial decay temperature range of all measured resistance-temperature change curves to the number of measured resistance-temperature change curves. This yields a reference weight for the lower limit of the lower limit. The lower limits of the initial decay trend segments of all measured resistance-temperature change curves are then weighted and averaged to obtain the result as the lower limit of the decay change lower limit.

[0075] Furthermore, the reciprocal of the difference between the upper limit and lower limit of the decay change temperature is used as the decay steepness coefficient; the product of 1 plus the decay steepness coefficient and the minimum temperature deviation of the initial decay temperature is used as the correction temperature deviation of the initial decay temperature, as shown in the following formula:

[0076]

[0077] In the formula, Minimum temperature deviation; The steepness coefficient.

[0078] It should be noted that the upper and lower limits of the decay change temperature are obtained by comprehensively analyzing the fluctuation performance of the initial decay change trend segment in multiple measurement results. The upper and lower limits of the decay change temperature are obtained by weighting these results. They initially reflect the overall trend of the initial decay change trend segment. The decay change steepness coefficient is then analyzed, which reflects the transition rate of the resistance-temperature change curve near the initial decay temperature. The faster the transition, the greater the minimum temperature deviation needs to be, so as to provide a basis for obtaining the initial decay temperature range in the future.

[0079] Thus, the corrected temperature deviation of the initial temperature attenuation is obtained.

[0080] Step S003: Based on the initial attenuation temperature and its corrected temperature deviation in the original resistance-temperature change curve, obtain the initial attenuation temperature range and compare the trend changes of the measured temperatures before and after removal to obtain the trend influence factor of each measured temperature; analyze the decimal fluctuation of the measured resistance in different measured resistance-temperature change curves to obtain the adjustment weight of each measured temperature, and obtain the adjusted initial attenuation temperature by weighting the initial attenuation temperature range; obtain the adjusted initial superconducting temperature.

[0081] It should be noted that after determining the corrected temperature deviation of the initial decay temperature, the temperature deviation is corrected based on the fluctuation of the initial decay temperature to obtain the initial decay temperature range. Then, a weighted adjustment is needed based on the initial decay temperature range to obtain the adjusted initial decay temperature. This requires first analyzing the trend of the measured temperature and then measuring the resistance fluctuation performance at the same measurement temperature under multiple measurements. The adjustment weights are then obtained and the adjustment is performed accordingly.

[0082] Preferably, in one embodiment of the present invention, based on the initial attenuation temperature and its corrected temperature deviation in the original resistance-temperature change curve, the initial attenuation temperature range is obtained, and the trend changes of the measured temperatures before and after removal are compared to obtain the trend influence factor of each measured temperature. The specific method includes:

[0083] The range obtained by adding or subtracting the corrected temperature deviation from the initial decay temperature in the original resistance-temperature curve is taken as the initial decay temperature range. The original resistance-temperature curve is then truncated at this initial decay temperature range; specifically, the section between the lower and upper limits of the initial decay temperature range is cut off from the original resistance-temperature curve and becomes the decay cutoff resistance-temperature curve. A vertical baseline is constructed using the upper temperature limit of the decay cutoff resistance-temperature curve, and a horizontal baseline is constructed using the minimum resistance value. This yields the original area of ​​the decay cutoff resistance-temperature curve (a monotonically decreasing curve). (The area is obtained by integration using the horizontal and vertical baselines). For any measured temperature within the initial attenuation temperature range, the data point corresponding to that measured temperature is removed. The original resistance-temperature change curve is then refitted based on other data points and truncated through the initial attenuation temperature range. The resulting curve segment is used as the truncated resistance-temperature change curve for that measured temperature. The area of ​​the truncated resistance-temperature change curve is obtained using the above method and is used as the truncated area for that measured temperature. The absolute value of the difference between the original area and the truncated area for that measured temperature is used as the trend influence factor for that measured temperature.

[0084] It should be noted that, since the resistance-temperature change curve has a hidden fitting process based on data points, after obtaining the initial temperature range of attenuation based on the corrected temperature deviation, in the process of trend analysis of each measured temperature in the initial temperature range of attenuation, the difference in area before and after removing the corresponding data points of the measured temperature is used to represent the trend. The larger the area difference, the greater its influence on the curve fitting, and the larger the corresponding trend influence factor.

[0085] Furthermore, the trend influence factors of each measured temperature in the initial attenuation temperature range are obtained according to the above method. It should be noted that if the upper or lower temperature limit of the initial attenuation temperature range is used as the measured temperature, it will normally participate in the above trend influence factor calculation. That is, since the attenuation cutoff resistance-temperature change curve is based on the attenuation initial temperature range cut off from the original resistance-temperature change curve, the corresponding temperature is not removed after removing the corresponding data points. The corresponding position is directly obtained by fitting, and the horizontal and vertical baselines and the eccentric area are obtained according to the above method.

[0086] It should be further explained that after determining the trend influence factor of each measured temperature in the initial attenuation temperature range, it reflects the trend influence of each measured temperature on the resistance-temperature change curve. It is necessary to further analyze the fluctuation performance of the measured resistance at the same measured temperature under multiple measurements. Since the initial attenuation temperature range is basically in the transition zone, its resistance change amplitude is small and presents as a decimal resistance change. Therefore, it is necessary to perform a decimal fluctuation analysis of the measured resistance at the same measured temperature, and use this to obtain the trend influence coefficient in combination with the trend influence factor. Then, it is used as the adjustment weight to adjust each measured temperature in the initial attenuation temperature range to obtain the adjusted initial attenuation temperature.

[0087] Preferably, in one embodiment of the present invention, the method of analyzing the decimal fluctuation of the measuring resistance in different measuring resistance-temperature change curves to obtain the adjustment weight of each measuring temperature, and weighting the initial attenuation temperature range to obtain the adjusted initial attenuation temperature, includes the following specific method:

[0088] For any identical measurement temperature in different resistance-temperature change curves, obtain the measurement resistance corresponding to that measurement temperature in different resistance-temperature change curves, and use these as several measurement resistances for that measurement temperature. All measurement resistances are split into integer and decimal places (all measurement resistance units are ohms, split into decimal places in ohm units). The decimal places of each measurement resistance corresponding to the mode of the integer places of all measurement resistances are used as the decimal place set for that measurement temperature. The variance of all decimal place data in the decimal place set of that measurement temperature is obtained as the resistance fluctuation coefficient of that measurement temperature. The sum of 1 and the resistance fluctuation coefficient is multiplied by the trend influence factor of that measurement temperature as the trend influence coefficient of that measurement temperature. The trend influence coefficients of each measurement temperature in the initial attenuation temperature range are obtained according to the above method. All trend influence coefficients are weighted and normalized, and the result is used as the adjustment weight for each measurement temperature. In this embodiment, the softmax function is used for weight normalization.

[0089] It should be noted that the greater the fluctuation of the decimal places of the measured resistance at the same measurement temperature, that is, the greater the variance of the decimal data, the greater the local fluctuation of the resistance. The greater the importance of the measurement temperature in the entire initial decay temperature range, so as to adjust the trend influence factor and assign more weight to it when adjusting the initial decay temperature in the future.

[0090] Furthermore, for each measured temperature within the initial attenuation temperature range, a weighted sum is calculated based on their respective adjustment weights, and the result is used as the adjusted initial attenuation temperature, such as... Figure 6 As shown.

[0091] Preferably, in one embodiment of the present invention, the specific method for obtaining the adjusted initial superconducting temperature is as follows:

[0092] For the initial superconducting temperature, following the adjustment method for the initial temperature decay, a proximity ratio is preset. In this embodiment, the proximity ratio is described as 0.1. The curve segment from the original resistance to zero resistance in the original resistance-temperature change curve is taken as the resistance proximity region. The slope of each data point in the resistance proximity region is calculated, and the average slope is taken as the resistance temperature coefficient of the proximity region. Then, the ratio of the minimum resistance deviation to the resistance temperature coefficient of the proximity region is taken as the minimum temperature deviation of the initial superconducting temperature. For any measured resistance-temperature change curve, the trend segment where the initial superconducting temperature is located in the measured resistance-temperature change curve is taken as the trend segment of the initial superconducting change of the measured resistance-temperature change curve. The upper and lower limits of the superconducting change temperature are obtained from this, and the steepness coefficient of the superconducting change is obtained. This is used to correct the minimum temperature deviation of the initial superconducting temperature, thus obtaining the corrected temperature deviation of the initial superconducting temperature.

[0093] Furthermore, based on the corrected temperature deviation of the superconducting initial temperature, the superconducting initial temperature range is obtained, and the superconducting cutoff resistance-temperature change curve is obtained accordingly. Then, the trend influence factor of each measured temperature is obtained. The decimal set of each measured temperature is obtained, the trend influence coefficient of each measured temperature is obtained, and the adjustment weight of each measured temperature is obtained. The adjusted superconducting initial temperature is obtained by weighting.

[0094] It should be noted that the overall processing of the superconducting initial temperature and the decay initial temperature is basically the same. The decay initial temperature involves the transition region from the original resistance to 0.9 times the original resistance, while the superconducting initial temperature is adjusted to the region near the zero resistance from 0.1 times the original resistance, thereby obtaining the minimum temperature deviation of the superconducting initial temperature. The superconducting initial change trend segment in the measured resistance-temperature change curve is screened, and the upper and lower limits of the superconducting change temperature are obtained in the same way to obtain the superconducting change steepness coefficient and correct the temperature deviation. The superconducting initial temperature range is obtained, and the trend influence factor and adjustment weight of each measured temperature are obtained. The weighted adjustment is then used to obtain the adjusted superconducting initial temperature.

[0095] Thus, the adjusted initial decay temperature and the adjusted initial superconductivity temperature are obtained, as follows: Figure 6 As shown.

[0096] Step S004: Based on the adjusted initial decay temperature and the adjusted initial superconducting temperature, obtain the critical temperature to realize the performance testing of copper oxide high-temperature superconductors.

[0097] The average of the adjusted initial decay temperature and the adjusted initial superconducting temperature is taken as the critical temperature of the copper oxide high-temperature superconductor. Figure 7As shown, the critical temperature of the copper oxide high-temperature superconductor is determined by identifying the critical temperature, and then the particle-hole asymmetry is tested based on the critical temperature, thereby realizing the performance testing of the copper oxide high-temperature superconductor.

[0098] This concludes the embodiment.

[0099] Another embodiment of the present invention provides a copper oxide high-temperature superconductor performance testing system. The system includes a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, it implements the above-described method steps S001 to S004.

[0100] In summary, the copper oxide high-temperature superconductor performance testing method provided by this invention is a test data processing method proposed to address the actual error sources and fluctuations in multiple measurements during the resistance method measurement process. Through multiple technological innovations, such as instrument error constraints, adaptive correction of transition steepness, and dual-weight reconstruction of trend and fluctuation, it achieves high robustness and high accuracy in determining the critical temperature under real measurement fluctuation environments, significantly improving the scientific rigor and engineering practicality of copper oxide high-temperature superconductor performance testing.

[0101] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for testing the performance of copper oxide high-temperature superconductors, characterized in that, Includes the following steps: The original resistance of the copper oxide high-temperature superconductor was obtained, and the measured resistance was obtained by adjusting the measurement temperature. The original resistance-temperature change curve and several measured resistance-temperature change curves were obtained. The initial decay temperature and the initial superconducting temperature are marked in the resistance-temperature change curve. Based on the slope changes of adjacent data points of the initial decay temperature in the original resistance-temperature change curve, the minimum temperature deviation of the initial decay temperature is obtained in combination with the original resistance. The differences in the slope changes of adjacent data points in the measured resistance-temperature change curve are analyzed, and the initial decay trend segment is selected. According to the distribution of the upper and lower limits of the initial decay trend segment in each measured resistance-temperature change curve among all initial decay trend segments, the decay steepness coefficient is obtained, and then the corrected temperature deviation of the initial decay temperature is obtained. Based on the initial decay temperature and its corrected temperature deviation in the original resistance-temperature change curve, the initial decay temperature range is obtained, and the trend changes of the measured temperatures before and after removal are compared to obtain the trend influence factor of each measured temperature. The decimal fluctuation of the measured resistance in different resistance-temperature change curves is analyzed to obtain the adjustment weight of each measured temperature. The initial decay temperature range is weighted to obtain the adjusted initial decay temperature. The adjusted initial superconducting temperature is then obtained. Based on the adjusted initial decay temperature and the adjusted initial superconducting temperature, the critical temperature is obtained, enabling performance testing of copper oxide high-temperature superconductors.

2. The method for testing the performance of a copper oxide high-temperature superconductor according to claim 1, characterized in that, The specific method for obtaining the minimum temperature deviation of the initial attenuation temperature is as follows: Obtain the range of a digital voltmeter and the range of the current source. ,Will and The ratio is taken as the minimum resistance deviation; A preset conversion ratio is used. The curve segment corresponding to the original resistance to the original resistance of the conversion ratio in the original resistance-temperature change curve is taken as the resistance conversion region. The slope of each data point in the resistance conversion region is calculated. The average of the slopes of all data points is taken as the resistance temperature coefficient of the conversion region. The ratio of the minimum resistance deviation to the resistance temperature coefficient of the conversion region is taken as the minimum temperature deviation of the initial temperature decay.

3. The method for testing the performance of copper oxide high-temperature superconductors according to claim 1, characterized in that, The specific method for obtaining the initial attenuation trend segment is as follows: For any resistance-temperature change curve, obtain the slope of all data points of the resistance-temperature change curve, preset the abrupt change ratio, and use the product of the abrupt change ratio and the mean of the slope of all data points of the resistance-temperature change curve as the abrupt change threshold of the resistance-temperature change curve. Obtain the absolute value of the difference in slope between adjacent data points. If the absolute value of the difference in slope is greater than the abrupt change threshold, take the data point corresponding to the minimum temperature among two adjacent data points as a segment point, obtain all segment points of the measured resistance-temperature change curve, obtain several trend segments of the measured resistance-temperature change curve based on the segment points, and take the trend segment where the initial temperature of the measured resistance-temperature change curve is located as the initial change trend segment of the measured resistance-temperature change curve.

4. The method for testing the performance of copper oxide high-temperature superconductors according to claim 1, characterized in that, The specific method for obtaining the attenuation steepness coefficient is as follows: Obtain the upper and lower temperature limits of the initial decay trend segment of any measured resistance-temperature change curve, and denote the closed interval formed by the lower and upper temperature limits as the initial decay temperature interval of the measured resistance-temperature change curve. Obtain the initial decay trend segment, upper and lower temperature limits, and initial decay temperature range for each measured resistance-temperature change curve. For the upper temperature limit of the initial decay trend segment of any measured resistance-temperature change curve, use the ratio of the number of times the upper temperature limit appears in the initial decay temperature range of all measured resistance-temperature change curves to the number of measured resistance-temperature change curves as the reference weight of the upper temperature limit. The upper temperature limit of the initial trend segment of the decay of all measured resistance-temperature change curves is weighted and averaged according to their respective reference weights, and the result is taken as the upper temperature limit of the decay change. Obtain the lower limit of the decay change temperature, and use the reciprocal of the difference between the upper limit of the decay change temperature and the lower limit of the decay change temperature as the decay change steepness coefficient.

5. The method for testing the performance of a copper oxide high-temperature superconductor according to claim 1, characterized in that, The specific method for obtaining the corrected temperature deviation of the initial attenuation temperature is as follows: The sum of 1 and the aforementioned attenuation steepness coefficient, multiplied by the minimum temperature deviation of the initial attenuation temperature, is used as the corrected temperature deviation of the initial attenuation temperature.

6. The method for testing the performance of a copper oxide high-temperature superconductor according to claim 1, characterized in that, The specific method for obtaining the initial attenuation temperature range is as follows: The range obtained by adding or subtracting the corrected temperature deviation from the initial temperature attenuation in the original resistance-temperature change curve is taken as the initial temperature attenuation range.

7. The method for testing the performance of copper oxide high-temperature superconductors according to claim 1, characterized in that, The specific method for obtaining the trend influence factors of each measured temperature is as follows: The original resistance-temperature change curve is truncated by the initial temperature range of attenuation to obtain a segment of the curve, which is then used as the attenuation cutoff resistance-temperature change curve. A vertical baseline is constructed using the upper temperature limit of the attenuation cutoff resistance-temperature change curve, and a horizontal baseline is constructed using the minimum resistance value, thus obtaining the original area of ​​the attenuation cutoff resistance-temperature change curve. For any measurement temperature within the initial attenuation temperature range, remove the data point corresponding to that measurement temperature, refit the original resistance-temperature change curve based on other data points, and truncate it using the initial attenuation temperature range. The resulting curve segment is used as the truncated resistance-temperature change curve for that measurement temperature. Obtain the area of ​​the truncated resistance-temperature change curve and use it as the truncated area for that measurement temperature. The absolute value of the difference between the original area and the truncated area for that measurement temperature is used as the trend influence factor for that measurement temperature.

8. The method for testing the performance of copper oxide high-temperature superconductors according to claim 1, characterized in that, The specific method for obtaining the adjusted weights of each measured temperature and then weighting the initial attenuation temperature range to obtain the adjusted initial attenuation temperature includes: For any identical measurement temperature in different resistance-temperature change curves, obtain the measurement resistance corresponding to that measurement temperature in different resistance-temperature change curves, and use it as several measurement resistances for that measurement temperature. Then, split all measurement resistances into integer and fractional parts, and use the fractional part of each measurement resistance corresponding to the mode of the integer parts of all measurement resistances as the set of fractional parts for that measurement temperature. Obtain the variance of all decimal data in the set of decimal places of the measured temperature, and use it as the resistance fluctuation coefficient of the measured temperature. Multiply the sum of 1 and the resistance fluctuation coefficient by the trend influence factor of the measured temperature, and use it as the trend influence coefficient of the measured temperature. Obtain the trend influence coefficient of each measured temperature in the initial temperature range of decay, normalize the weight of all trend influence coefficients, and use the result as the adjustment weight of each measured temperature. For each measured temperature in the initial decay temperature range, a weighted sum is calculated based on their respective adjustment weights, and the result is used as the adjusted initial decay temperature.

9. The method for testing the performance of a copper oxide high-temperature superconductor according to claim 8, characterized in that, The adjusted initial superconducting temperature is obtained using the following method: A proximity ratio is preset, and the curve segment from the original resistance to zero resistance in the original resistance-temperature change curve is taken as the resistance proximity region. The slope of each data point in the resistance proximity region is calculated, and the average slope is taken as the resistance temperature coefficient of the proximity region. Then, the ratio of the minimum resistance deviation to the resistance temperature coefficient of the proximity region is taken as the minimum temperature deviation of the superconducting initial temperature. For any measured resistance-temperature change curve, the trend segment where the superconducting initial temperature is located in the measured resistance-temperature change curve is taken as the superconducting initial change trend segment of the measured resistance-temperature change curve. The upper and lower limits of the superconducting change temperature are obtained from this, and then the superconducting change steepness coefficient is obtained. This coefficient is used to correct the minimum temperature deviation of the superconducting initial temperature, and the corrected temperature deviation of the superconducting initial temperature is obtained. Based on the corrected temperature deviation of the superconducting initial temperature, the superconducting initial temperature range is obtained, and the superconducting cutoff resistance-temperature change curve is obtained from it. Then, the trend influence factor of each measured temperature is obtained. The decimal set of each measured temperature is obtained, the trend influence coefficient of each measured temperature is obtained, and then the adjustment weight of each measured temperature is obtained. The weighted average is then used to obtain the adjusted superconducting initial temperature.

10. A copper oxide high-temperature superconductor performance testing system, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the copper oxide high-temperature superconductor performance testing method as described in any one of claims 1-9.

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