Method for monitoring and analyzing sources of contaminants in a hydraulic lubrication system

Abstract

The application discloses a kind of monitoring analysis methods of contaminant source in hydraulic lubrication system, it is related to hydraulic lubrication system monitoring field, this contaminant source monitoring analysis method includes the following steps: S100, preparation of quantum dot fluorescent probe: design and synthesis for the quantum dot fluorescent probe of oxidation contaminant in hydraulic lubrication system, by surface modification and ligand selection of quantum dot, it can be specifically combined with target contaminant and produce significant fluorescence change, the specific quantum dot fluorescent probe for the oxidation contaminant in hydraulic lubrication system is designed and synthesized in the application, realizes the accurate detection of trace contaminant in oil, significantly enhances the detection sensitivity of target contaminant, in addition, by surface functionalization modification, quantum dot fluorescent probe can be specifically combined with target contaminant, produce significant fluorescence change, to improve the accuracy of detection.

Description

Technical Field

[0001] The present invention relates to the technical field of medical image processing, and in particular to a method for monitoring and analyzing sources of pollutants in a hydraulic lubrication system. Background Art

[0002] Hydraulic lubrication systems play a vital role in many industrial fields, such as machinery manufacturing, aerospace, and the automotive industry. They can reduce friction, lower wear, transmit power, and ensure stable operation of equipment. However, various pollutants are inevitably generated during system operation. The presence of these pollutants poses a serious threat to the performance, reliability, and life of the system.

[0003] Currently, monitoring of contaminants in hydraulic lubrication systems mainly relies on physical filtration and chemical analysis methods. Although physical filtration can remove larger particles of contaminants, it is powerless to detect trace harmful compounds. Although chemical analysis methods can provide detailed information about contaminants, they usually require complex sample pretreatment, professional operators and expensive analytical equipment, and the analysis cycle is long, which cannot meet the needs of real-time monitoring. In particular, for the detection of trace contaminants such as oxidation products, existing technologies lack sufficient sensitivity and selectivity, making it difficult to achieve rapid and accurate monitoring.

[0004] In summary, the existing hydraulic lubrication system pollutant monitoring methods have many problems in terms of efficiency, accuracy and adaptability, and cannot meet the modern industry's demand for high-precision, real-time and reliable pollutant monitoring. Therefore, the development of a hydraulic lubrication system pollutant source monitoring and analysis method based on optimized quantum dot fluorescent probes has important practical significance and application value. Summary of the Invention

[0005] The purpose of the present invention is to make up for the shortcomings of the existing technology and provide a method for monitoring and analyzing the sources of pollutants in a hydraulic lubrication system. It can accurately detect specific harmful compounds (oxidation products) in the oil by designing a quantum dot fluorescent probe with a specific response, and further analyze the source of the pollutants. This method not only has the advantages of high sensitivity, high selectivity and low cost, but also can realize real-time monitoring and online analysis, providing strong support for the operation and maintenance of the hydraulic lubrication system.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: a method for monitoring and analyzing the sources of pollutants in a hydraulic lubrication system, the method comprising the following steps:

[0007] S100, Preparation of Quantum Dot Fluorescent Probes: Design and synthesis of quantum dot fluorescent probes targeting oxidative pollutants in hydraulic lubrication systems. Through surface modification and ligand selection, the quantum dots are able to specifically bind to the target pollutants and produce significant fluorescence changes.

[0008] S200, probe introduction and distribution: The prepared quantum dot fluorescent probe is introduced into the oil of the hydraulic lubrication system by microinjection. During the operation of the system, the probe is evenly distributed in the oil by the flow and stirring of the oil;

[0009] S300, establishes an accurate quantitative relationship model: prepare oil samples with known concentrations of target pollutants, add quantum dot fluorescent probes to each sample for detection, obtain fluorescence signal change data, and establish a quantitative relationship equation between the fluorescence signal change and pollutant concentration through statistical analysis and mathematical fitting of the data;

[0010] S400, specific detection of quantum dot fluorescent probes: using a fluorescence spectrophotometer to perform fluorescence detection on the mixed sample, the presence of the target pollutant is determined by measuring the change in fluorescence intensity, and the concentration of the pollutant is estimated based on the degree of change in fluorescence intensity;

[0011] S500, Pollutant Source Tracing and Analysis: Analyze the source of pollutants based on the changes in fluorescent signals detected at different locations, combined with the structure and working principle of the hydraulic lubrication system.

[0012] Furthermore, the specific steps of S100 are:

[0013] S101, selection of semiconductor materials: selecting semiconductor materials, namely, cadmium selenide and cadmium sulfide, and preparing quantum dots with particle size and luminescence properties through chemical synthesis;

[0014] S102, Chemical Synthesis of Quantum Dots: Using the hot injection method, by precisely controlling the reaction temperature, reaction time, and precursor concentration, the quantum dots are uniformly distributed in size and have a regular morphology. The surface state of the quantum dots is further optimized by adjusting the reaction solvent and surfactant.

[0015] S103, surface functionalization modification: Through surface modification technology, that is, using polyethylene glycol and thioglycolic acid substances to modify the surface of quantum dots, molecules and groups that can specifically identify target oxidized pollutants are introduced to form specifically responsive quantum dot fluorescent probes.

[0016] Furthermore, in order to realize the specific recognition of oxidized pollutants by quantum dot fluorescent probes, the S103 functionally modifies the surface of quantum dots. The modification strategies include electrostatic adsorption, covalent coupling and ligand exchange. Molecules and groups that have specific interactions with target pollutants are selected as recognition units, which are connected to the quantum dot surface by chemical bonding and physical adsorption. The recognition units form stable complexes with the target pollutants, and the significant changes in the fluorescence properties of the quantum dots, i.e., fluorescence quenching and enhancement, are analyzed to specifically detect oxidized pollutants.

[0017] Furthermore, the specific steps of S102 are:

[0018] S102.1. Reaction conditions: Synthesize quantum dots by hot injection under inert gas protection, with a reaction temperature of 200°C to 300°C, a reaction time of 2 hours to 5 hours, and a precursor concentration of 0.01 M to 0.1 M.

[0019] S102.2, selection of reaction solvent and surfactant: use a mixed solvent of trioctylphosphine oxide (TOPO) and a selenium source, where the volume ratio of TOPO to selenium source is 6:1. By adjusting the surfactant, thioglycolic acid (MUA) is selected as the surface modifier, and the molar ratio of MUA to quantum dots is 1:50 to optimize the solubility and biocompatibility of quantum dots.

[0020] Furthermore, the specific steps of S200 are:

[0021] S201, preparing a probe solution: dispersing the prepared quantum dot fluorescent probe in a dimethylformamide solvent to form a uniform and stable probe solution;

[0022] S202, microinjection: Use a microsyringe to inject the probe solution into the oil circulation of the hydraulic lubrication system. The injection speed is controlled at 0.1 to 1 ml / min. At the same time, ensure that the injection volume does not significantly affect the normal operation of the system.

[0023] S203, uniform distribution: During the operation of the system, the injected quantum dot fluorescent probe is evenly distributed in the oil by utilizing the circulation of the oil and the stirring device in the system. The distribution time is 5 to 30 minutes, so that the oil in the entire system can be effectively monitored;

[0024] S204, cyclic monitoring: After the probe distribution is completed, the quantum dot fluorescent probe in the oil is monitored in real time to prepare for the subsequent specific detection step.

[0025] Furthermore, the specific steps of S300 are:

[0026] S301, Standard Solution Preparation: Use high-precision measuring instruments to prepare oil samples of target pollutants with known concentrations, covering the concentration range of pollutants present in the oil to be tested;

[0027] S302, probe addition and mixing: adding an equal amount of quantum dot fluorescent probe to each standard solution, and stirring and shaking to fully mix the probe and target pollutant;

[0028] S303, fluorescence detection: using a fluorescence spectrophotometer to perform fluorescence detection on the mixed sample, recording the fluorescence spectrum of the sample at each concentration, paying particular attention to changes in fluorescence intensity;

[0029] S304, data analysis and fitting: statistically analyzing the detected fluorescence signal change data, i.e., the fluorescence intensity and the concentration of the target pollutant, to establish a quantitative relationship equation between the fluorescence signal change and the pollutant concentration, and verifying its accuracy and reliability;

[0030] S305, model verification and optimization: verify the accuracy of the established quantitative relationship model through independent standard solutions, and adjust and optimize the model parameters.

[0031] Furthermore, the step S305 collects data of standard solutions of different concentrations, measures the change in fluorescence intensity corresponding to each concentration, establishes a quantitative relationship model between the fluorescence signal and the pollutant concentration, and predicts the pollutant concentration from the change in fluorescence intensity. The specific steps are as follows:

[0032] Data collation: The obtained fluorescence intensity data is F, and the pollutant concentration data is C. Perform preliminary statistical analysis on the data to understand the distribution characteristics of the data;

[0033] Quantitative relationship model construction: For the linear relationship between fluorescence intensity change F and pollutant concentration C, the objective function of the quantitative relationship model is established, that is, F = aC + b, where a is the slope, which represents the rate of change of fluorescence intensity caused by concentration change, and b is the intercept, that is, the fluorescence intensity value when C = 0;

[0034] Parameter estimation: Fluorescence detection is performed on the sample after S303 mixing, that is, the sample data is marked as (C1, F1), (C2, F2), ..., (C n ,F n ), using the sample data to minimize the residual sum of squares, thus finding the best fitting line, that is,

[0035] Parameter solution: solve the slope a and intercept b, that is

[0036] Model application: Using the established model, for the new fluorescence intensity change value F new, calculate the pollutant concentration C by reverse solution new ,Right now

[0037] Furthermore, the specific steps of S400 are:

[0038] S401, Sample Preparation: Collect oil samples from different parts of the hydraulic lubrication system so that the samples can represent different contamination conditions of the system;

[0039] S402, probe addition: adding quantum dot fluorescent probes to each oil sample and performing pretreatment, i.e., filtering and centrifuging, to remove large particle impurities that interfere with fluorescence detection;

[0040] S403, Mixing Reaction and Fluorescence Detection: Thoroughly mix the quantum dot fluorescent probe and the oil sample by stirring and shaking. Perform fluorescence detection on the mixed sample using a fluorescence spectrophotometer, record the fluorescence spectrum, and pay special attention to changes in fluorescence intensity.

[0041] S404, data analysis: analyzing the fluorescence spectrum to analyze the changes in the fluorescence signal, including measuring the fluorescence intensity, determining the fluorescence peak position, and calculating the fluorescence lifetime;

[0042] S405, result comparison: the detected fluorescence data is compared with the standard curve established in S300, and the presence of the target pollutant is determined based on the change in fluorescence intensity, and its concentration is evaluated.

[0043] Furthermore, in the data analysis process of S404, the steps of calculating the fluorescence intensity, the fluorescence peak position and the fluorescence lifetime are as follows:

[0044] S404.1, Measurement of Fluorescence Intensity: The fluorescence emission spectrum of the mixed oil sample at the excitation wavelength is directly read by a fluorescence spectrophotometer. The maximum value of the fluorescence spectrum is the fluorescence intensity F max ;

[0045] S404.2, Determination of fluorescence peak position: The wavelength corresponding to the maximum fluorescence intensity in the fluorescence spectrum is determined by analyzing the fluorescence spectrum, automatically identifying and manually calibrating the fluorescence peak position;

[0046] S404.3, Calculation of fluorescence lifetime: The fluorescence lifetime τ describes the time required for a fluorescent molecule to return from an excited state to a ground state. It is estimated based on the decay characteristics of fluorescence intensity. That is, the formula for the decay of fluorescence intensity over time t is: F(t) is the fluorescence intensity at time t, F0 is the initial fluorescence intensity, that is, the fluorescence intensity at t = 0, and the response time t is fixed during the measurement process. resp During this time, the fluorescence intensity increases from Finit Decay to F mea s , then the fluorescence lifetime estimation formula is

[0047] Furthermore, the specific steps of S500 are:

[0048] S501, data collection and collation: collecting fluorescence detection data from different monitoring points in the hydraulic lubrication system, namely, the oil tank, oil pump inlet, oil pump outlet, and each branch pipeline;

[0049] S502, fluorescence signal comparison analysis: Compare the fluorescence signal of each monitoring point with the standard curve established in S300 to determine the presence or absence of pollutants at each point and their relative concentrations. Compare the fluorescence signal differences between different monitoring points to identify areas and locations where the fluorescence signal is significantly enhanced.

[0050] S503, System Structure and Operating Principle Analysis: Based on the structural layout of the hydraulic lubrication system, the oil flow path, and the operating principles of each component, analyze the correlation between areas of significantly enhanced fluorescence signals and potential sources of contamination within the system, such as seal wear, oil oxidation reaction areas, and external contaminant intrusion points;

[0051] S504, Pollutant Source Inference: Based on a comprehensive analysis of the distribution characteristics of the fluorescence signal, system structure, and working principle, the source of the pollutant is inferred;

[0052] S505, Verification and Feedback: Based on the inferred source of contaminants, formulate corresponding inspection and maintenance plans, verify and clean up the suspected contamination sources, and provide feedback on the monitoring and analysis results to continuously optimize the operation and maintenance strategy of the hydraulic lubrication system.

[0053] Compared with the existing technology, this method for monitoring and analyzing the source of pollutants in a hydraulic lubrication system has the following beneficial effects:

[0054] 1. The present invention designs and synthesizes specific quantum dot fluorescent probes for oxidative pollutants in hydraulic lubrication systems, achieving accurate detection of trace pollutants in the oil. Due to its unique quantum size effect and surface effect, the quantum dot fluorescent probe has extremely high fluorescence quantum yield and photostability, which can significantly enhance the detection sensitivity of target pollutants. In addition, through surface functionalization modification, the quantum dot fluorescent probe can specifically bind to the target pollutant, producing significant fluorescence changes, thereby improving the accuracy of detection. This highly sensitive and accurate monitoring method enables trace pollutants in the hydraulic lubrication system, such as oxidation products, to be detected in a timely and accurate manner, providing reliable data support for system maintenance and care.

[0055] 2. The method of the present invention is not limited to the detection of pollutants, but also realizes the tracing of the source of pollutants through real-time monitoring and data analysis. In the hydraulic lubrication system, the quantum dot fluorescent probe is introduced into the oil by microinjection, and the probe is evenly distributed in the oil with the help of the flow and stirring of the oil. Subsequently, the mixed sample is subjected to fluorescence detection by a fluorescence spectrophotometer, and the presence of the target pollutant is judged by measuring the change in fluorescence intensity, and its concentration is evaluated. More importantly, by collecting fluorescence detection data from different monitoring points in the hydraulic lubrication system and combining the analysis of the system structure and working principle, the source of the pollutant is inferred. This real-time monitoring and source tracing capability enables system maintenance personnel to quickly locate the source of pollution and take targeted measures for cleaning and maintenance, thereby effectively extending the service life of the hydraulic lubrication system and reducing maintenance costs.

[0056] Other advantages, objects and features of the present invention will be described in part in the following description and, in part, will be apparent to those skilled in the art based on an examination of the following or may be learned from the practice of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0058] Figure 1 The present invention is an operational flow chart of a method for monitoring and analyzing the sources of pollutants in a hydraulic lubrication system.

[0059] Figure 2 Flow chart of the steps for specific detection of S400 quantum dot fluorescent probe. DETAILED DESCRIPTION

[0060] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0061] Example 1

[0062] A method for monitoring and analyzing the sources of pollutants in a hydraulic lubrication system. This method significantly improves the sensitivity and selectivity of pollutant monitoring in the hydraulic lubrication system by using quantum dot fluorescent probes. Due to their unique size effect and surface properties, quantum dots can detect target pollutants at very low concentrations. Surface functionalization modification enables quantum dots to specifically identify specific types of pollutants, such as oxidation products. This specificity and high sensitivity help to detect potential problems in the system at an early stage, thereby reducing equipment failures and maintenance costs caused by pollutant accumulation.

[0063] First, the quantum dot fluorescent probe is prepared (S100). A mixed solvent of trioctylphosphine oxide (TOPO) and a selenium source is used, wherein the volume ratio of TOPO to the selenium source is 6:1. After the reaction is completed, the quantum dot precipitate is obtained by centrifugation and washed several times with anhydrous ethanol to remove excess TOPO. Thioglycolic acid (MUA) is selected as a surface modifier, and the molar ratio of MUA to quantum dots is 1:50. The quantum dots are dispersed in an ethanol solution containing MUA, and the reaction is stirred overnight to allow MUA to be connected to the quantum dot surface through ligand exchange, thereby optimizing its solubility and biocompatibility. Molecules that can specifically identify oxidative pollutants (organic molecules with specific functional groups) are connected to the MUA-modified quantum dot surface through covalent coupling to form a specifically responsive quantum dot fluorescent probe.

[0064] Then, the probe introduction and distribution stage (S200) is entered, and the prepared quantum dot fluorescent probe is dispersed in dimethylformamide solvent to prepare a probe solution of appropriate concentration. A micro syringe is used to inject the probe solution into the oil circulation of the hydraulic lubrication system at an injection rate of 0.5 ml / min. After the system has been running for 15 minutes, the quantum dot fluorescent probe is evenly distributed in the oil. Thereafter, the probe in the oil is continuously monitored in a circulation manner.

[0065] Next, enter the stage of establishing an accurate quantitative relationship model (S300). Use high-precision measuring instruments to prepare a series of oxidation product oil samples with known concentrations, ranging from 0.1ppm to 10ppm. Add an equal amount of quantum dot fluorescent probe to each standard solution, and stir and oscillate to fully mix the probe and the target pollutant. Use a fluorescence spectrophotometer to perform fluorescence detection on the mixed sample, record the fluorescence spectrum of the sample at each concentration, and pay special attention to the change in fluorescence intensity. Perform statistical analysis on the detected fluorescence signal change data, that is, the fluorescence intensity and the concentration of the target pollutant, establish a quantitative relationship equation between the fluorescence signal change and the pollutant concentration, and verify its accuracy and reliability. Collect standard solution data of different concentrations, establish a quantitative relationship model between the fluorescence signal and the pollutant concentration, verify the accuracy of the established quantitative relationship model through independent standard solutions, and adjust and optimize the model parameters.

[0066] Secondly, enter the specific detection stage of quantum dot fluorescent probe (S400), collect oil samples from different parts of the hydraulic lubrication system, add quantum dot fluorescent probe to each oil sample, and perform pretreatment, i.e., filtration and centrifugation to remove large particle impurities that interfere with fluorescence detection. The quantum dot fluorescent probe and the oil sample are fully mixed by stirring and oscillation. The mixed sample is subjected to fluorescence detection using a fluorescence spectrophotometer, and the fluorescence spectrum is recorded, with special attention paid to the change in fluorescence intensity. The fluorescence intensity is measured, the fluorescence peak position is determined, and the fluorescence lifetime is calculated. The fluorescence spectrum is analyzed, including the measurement of fluorescence intensity, the determination of fluorescence peak position, and the calculation of fluorescence lifetime. The detected fluorescence data is compared with the standard curve established in S300. The presence or absence of the target pollutant is judged based on the change in fluorescence intensity, and its concentration is evaluated.

[0067] Finally, the pollutant source tracing and analysis phase (S500) is entered, and the fluorescence detection data of each monitoring point is compared with the established standard curve. For example, it is found that the pollutant concentration at the oil pump outlet is significantly higher than that at other parts. Combined with the structure and working principle of the system, it is inferred that the wear inside the oil pump has led to an increase in oxidation products. An inspection and maintenance plan is formulated, and the oil pump is disassembled and inspected to verify the inference of the pollutant source. After cleaning and replacing the worn seals, the monitoring is carried out again, and the monitoring and analysis results are fed back to optimize the system's operation and maintenance strategy and increase the frequency of regular inspections of the oil pump.

[0068] In summary, this embodiment provides a method for monitoring and analyzing the sources of pollutants in a hydraulic lubrication system. Since the quantum dot fluorescent probe has high sensitivity and high selectivity, it can quickly and accurately detect trace pollutants in the hydraulic oil, especially oxidation products. This monitoring method significantly improves the efficiency and accuracy of pollutant detection. Compared with traditional physical filtration and chemical analysis methods, it reduces monitoring time and cost, while improving the operating reliability and production efficiency of the equipment.

[0069] Example 2

[0070] This embodiment provides a method for monitoring and analyzing the sources of pollutants in a hydraulic lubrication system, with particular emphasis on the specific implementation process of establishing an accurate quantitative relationship model and specific detection of quantum dot fluorescent probes, to demonstrate how to use quantum dot fluorescent probes for quantitative analysis and detection of pollutants.

[0071] Using high-precision measuring instruments, a series of oil samples with known concentrations of target pollutants are accurately prepared. The concentration range covers the possible pollutant concentrations in the oil to be tested, for example, from 0.05ppm to 5ppm. An equal amount of quantum dot fluorescent probe is added to each standard solution, and the samples are thoroughly mixed with the target pollutants through stirring and oscillation. The mixed samples are then subjected to fluorescence detection using a fluorescence spectrophotometer. During the detection process, the fluorescence spectra of the samples at various concentrations are recorded, with particular attention paid to changes in fluorescence intensity. The obtained fluorescence intensity data is F, and the pollutant concentration data is C. A preliminary statistical analysis is performed on these data to understand their distribution characteristics.

[0072] Then, based on the linear relationship between the fluorescence intensity change F and the pollutant concentration C, the objective function of the quantitative relationship model is established as F = aC + b, where a is the slope, which represents the rate of change of fluorescence intensity caused by concentration change, and b is the intercept, that is, the fluorescence intensity value when C = 0. In order to find the best fitting line, the sample data are marked as (C1, F1), (C2, F2), ..., (C n ,F n ), using sample data to minimize the residual sum of squares, that is Solve for the slope a and intercept b, the formula is The established quantitative relationship model is verified by independent standard solutions to ensure its accuracy and reliability. Based on the verification results, the model parameters are adjusted and optimized to improve the accuracy of the model.

[0073] Representative oil samples were collected from different parts of the hydraulic lubrication system, such as the oil tank, oil pump inlet, oil pump outlet, and various branch pipes, to ensure that the samples could reflect the different contamination conditions of the system. Quantum dot fluorescent probes were added to each oil sample and pre-treated, including filtration and centrifugation, to remove large particles that interfered with fluorescence detection. The quantum dot fluorescent probes and oil samples were fully mixed by stirring and oscillation. The mixed samples were subjected to fluorescence detection using a fluorescence spectrophotometer, and the fluorescence spectra were recorded, with special attention paid to changes in fluorescence intensity. During the data analysis process, the fluorescence intensity was measured by directly reading the fluorescence emission spectrum of the mixed oil sample at the excitation wavelength using a fluorescence spectrophotometer, where the maximum value of the fluorescence spectrum was the fluorescence intensity F. max The fluorescence peak position is determined by analyzing the fluorescence spectrum, automatically identifying and manually calibrating the wavelength corresponding to the maximum fluorescence intensity. The fluorescence lifetime is estimated by combining the decay characteristics of the fluorescence intensity. The formula for the decay of fluorescence intensity over time is: F(t) is the fluorescence intensity at time t, F0 is the initial fluorescence intensity, that is, the fluorescence intensity at t = 0, and the response time t is fixed during the measurement process. resp During this time, the fluorescence intensity increases from F init Decay to F mea s , then the fluorescence lifetime estimation formula is By analyzing the fluorescence spectrum, measuring the fluorescence intensity, determining the fluorescence peak position and calculating the fluorescence lifetime, the detected fluorescence data is compared with the standard curve established in S300. The presence of the target pollutant is determined based on the change in fluorescence intensity, and its concentration is evaluated. This step combines the quantitative relationship model and fluorescence detection data to achieve accurate detection and concentration assessment of pollutants.

[0074] In summary, this example demonstrates in detail the implementation process of steps S300 and S400. By establishing a precise quantitative relationship model and performing specific detection using quantum dot fluorescent probes, it successfully achieves real-time monitoring and accurate assessment of contaminants in the hydraulic lubrication system. This method not only improves the sensitivity and accuracy of contaminant monitoring but also provides strong data support for system maintenance and upkeep.

[0075] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. A method for monitoring and analyzing the source of pollutants in a hydraulic lubrication system, characterized in that: The pollutant source monitoring and analysis method comprises the following steps: S100, Preparation of Quantum Dot Fluorescent Probes: Design and synthesis of quantum dot fluorescent probes targeting oxidative pollutants in hydraulic lubrication systems. Through surface modification and ligand selection, the quantum dots are able to specifically bind to the target pollutants and produce significant fluorescence changes. S200, Probe Introduction and Distribution: Prepared quantum dot fluorescent probes are introduced into the oil of the hydraulic lubrication system via microinjection. During system operation, the probes are evenly distributed in the oil by virtue of the flow and stirring of the oil. To achieve specific recognition of oxidized pollutants by the quantum dot fluorescent probes, the quantum dot surface is functionalized. Modification strategies include electrostatic adsorption, covalent coupling, and ligand exchange. Molecules and groups that specifically interact with the target pollutants are selected as recognition units and attached to the quantum dot surface through chemical bonding and physical adsorption. The recognition units form stable complexes with the target pollutants, and significant changes in the quantum dot fluorescence properties, namely fluorescence quenching and enhancement, are analyzed to enable specific detection of oxidized pollutants. S300, establishes an accurate quantitative relationship model: prepare oil samples with known concentrations of target pollutants, add quantum dot fluorescent probes to each sample for detection, obtain fluorescence signal change data, and establish a quantitative relationship equation between the fluorescence signal change and pollutant concentration through statistical analysis and mathematical fitting of the data; S400, specific detection of quantum dot fluorescent probes: using a fluorescence spectrophotometer to perform fluorescence detection on the mixed sample, the presence of the target pollutant is determined by measuring the change in fluorescence intensity, and the concentration of the pollutant is estimated based on the degree of change in fluorescence intensity; S500, pollutant source tracing and analysis: Based on the changes in the fluorescent signals detected at different locations and combined with the structure and working principle of the hydraulic lubrication system, the source of the pollutants is analyzed. The specific steps of S500 are as follows: S501, data collection and collation: collecting fluorescence detection data from different monitoring points in the hydraulic lubrication system, namely, the oil tank, oil pump inlet, oil pump outlet, and each branch pipeline; S502, fluorescence signal comparison analysis: Compare the fluorescence signal of each monitoring point with the standard curve established in S300 to determine the presence or absence of pollutants at each point and their relative concentrations. Compare the fluorescence signal differences between different monitoring points to identify areas and locations where the fluorescence signal is significantly enhanced. S503, System Structure and Operating Principle Analysis: Based on the structural layout of the hydraulic lubrication system, the oil flow path, and the operating principles of each component, analyze the correlation between areas of significantly enhanced fluorescence signals and potential sources of contamination within the system, such as seal wear, oil oxidation reaction areas, and external contaminant intrusion points; S504, Pollutant Source Inference: Based on a comprehensive analysis of the distribution characteristics of the fluorescence signal, system structure, and working principle, the source of the pollutant is inferred; S505, Verification and Feedback: Based on the inferred source of contaminants, formulate corresponding inspection and maintenance plans, verify and clean up the suspected contamination sources, and provide feedback on the monitoring and analysis results to continuously optimize the operation and maintenance strategy of the hydraulic lubrication system.

2. The method for monitoring and analyzing the source of pollutants in a hydraulic lubrication system according to claim 1, characterized in that: The specific steps of S100 are: S101, selection of semiconductor materials: selecting semiconductor materials, namely, cadmium selenide and cadmium sulfide, and preparing quantum dots with particle size and luminescence properties through chemical synthesis; S102, Chemical Synthesis of Quantum Dots: Using the hot injection method, by precisely controlling the reaction temperature, reaction time, and precursor concentration, the quantum dots are uniformly distributed in size and have a regular morphology. The surface state of the quantum dots is further optimized by adjusting the reaction solvent and surfactant. S103, surface functionalization modification: Through surface modification technology, that is, using polyethylene glycol and thioglycolic acid substances to modify the surface of quantum dots, molecules and groups that can specifically identify target oxidized pollutants are introduced to form specifically responsive quantum dot fluorescent probes.

3. The method for monitoring and analyzing the source of pollutants in a hydraulic lubrication system according to claim 1, characterized in that: The specific steps of S102 are: S102.

1. Reaction conditions: Synthesize quantum dots by hot injection under inert gas protection, with a reaction temperature of 200°C to 300°C, a reaction time of 2 hours to 5 hours, and a precursor concentration of 0.01 M to 0.1 M. S102.2, selection of reaction solvent and surfactant: use a mixed solvent of trioctylphosphine oxide (TOPO) and a selenium source, where the volume ratio of TOPO to selenium source is 6:

1. By adjusting the surfactant, thioglycolic acid (MUA) is selected as the surface modifier, and the molar ratio of MUA to quantum dots is 1:50 to optimize the solubility and biocompatibility of quantum dots.

4. The method for monitoring and analyzing the source of pollutants in a hydraulic lubrication system according to claim 1, characterized in that: The specific steps of S200 are: S201, preparing a probe solution: dispersing the prepared quantum dot fluorescent probe in a dimethylformamide solvent to form a uniform and stable probe solution; S202, microinjection: Use a microsyringe to inject the probe solution into the oil circulation of the hydraulic lubrication system. The injection speed is controlled at 0.1 to 1 ml / min. At the same time, ensure that the injection volume does not significantly affect the normal operation of the system. S203, uniform distribution: During the operation of the system, the injected quantum dot fluorescent probe is evenly distributed in the oil by utilizing the circulation of the oil and the stirring device in the system. The distribution time is 5 to 30 minutes, so that the oil in the entire system can be effectively monitored; S204, cyclic monitoring: After the probe distribution is completed, the quantum dot fluorescent probe in the oil is monitored in real time to prepare for the subsequent specific detection step.

5. The method for monitoring and analyzing the source of pollutants in a hydraulic lubrication system according to claim 1, characterized in that: The specific steps of S300 are: S301, Standard Solution Preparation: Use high-precision measuring instruments to prepare oil samples of target pollutants with known concentrations, covering the concentration range of pollutants present in the oil to be tested; S302, probe addition and mixing: adding an equal amount of quantum dot fluorescent probe to each standard solution, and stirring and shaking to fully mix the probe and target pollutant; S303, fluorescence detection: using a fluorescence spectrophotometer to perform fluorescence detection on the mixed sample, recording the fluorescence spectrum of the sample at each concentration, paying particular attention to changes in fluorescence intensity; S304, data analysis and fitting: statistically analyzing the detected fluorescence signal change data, i.e., the fluorescence intensity and the concentration of the target pollutant, to establish a quantitative relationship equation between the fluorescence signal change and the pollutant concentration, and verifying its accuracy and reliability; S305, model verification and optimization: verify the accuracy of the established quantitative relationship model through independent standard solutions, and adjust and optimize the model parameters.

6. The method for monitoring and analyzing the source of pollutants in a hydraulic lubrication system according to claim 1, characterized in that: The step S305 collects data of standard solutions of different concentrations, measures the change in fluorescence intensity corresponding to each concentration, establishes a quantitative relationship model between the fluorescence signal and the pollutant concentration, and predicts the pollutant concentration from the change in fluorescence intensity. The specific steps are as follows: Data collation: The obtained fluorescence intensity data is F, and the pollutant concentration data is C. Perform preliminary statistical analysis on the data to understand the distribution characteristics of the data; Quantitative relationship model construction: For the linear relationship between the fluorescence intensity change F and the pollutant concentration C, the objective function of the quantitative relationship model is established, that is, , is the slope, which indicates the rate of change of fluorescence intensity caused by concentration change. is the intercept, i.e., the fluorescence intensity value when C = 0; Parameter estimation: Fluorescence detection is performed on the sample after S303 mixing, that is, the sample data is marked as , use the sample data to minimize the residual sum of squares to find the best fitting line, that is, S= ; Parameter solution: Slope and intercept Solve it, that is , ; Model application: Using the established model, for new fluorescence intensity change values , calculate the pollutant concentration by reverse solution ,Right now .

7. The method for monitoring and analyzing the source of pollutants in a hydraulic lubrication system according to claim 1, characterized in that: The specific steps of S400 are: S401, Sample Preparation: Collect oil samples from different parts of the hydraulic lubrication system so that the samples can represent different contamination conditions of the system; S402, probe addition: adding quantum dot fluorescent probes to each oil sample and performing pretreatment, i.e., filtering and centrifuging, to remove large particle impurities that interfere with fluorescence detection; S403, Mixing Reaction and Fluorescence Detection: Thoroughly mix the quantum dot fluorescent probe and the oil sample by stirring and shaking. Perform fluorescence detection on the mixed sample using a fluorescence spectrophotometer, record the fluorescence spectrum, and pay special attention to changes in fluorescence intensity. S404, data analysis: analyzing the fluorescence spectrum to analyze the changes in the fluorescence signal, including measuring the fluorescence intensity, determining the fluorescence peak position, and calculating the fluorescence lifetime; S405, result comparison: the detected fluorescence data is compared with the standard curve established in S300, and the presence of the target pollutant is determined based on the change in fluorescence intensity, and its concentration is evaluated.

8. The method for monitoring and analyzing the source of pollutants in a hydraulic lubrication system according to claim 7, characterized in that: During the data analysis step S404, the steps of calculating the fluorescence intensity, the fluorescence peak position, and the fluorescence lifetime are as follows: S404.1, Measurement of Fluorescence Intensity: The fluorescence emission spectrum of the mixed oil sample at the excitation wavelength is directly read by a fluorescence spectrophotometer. The maximum value of the fluorescence spectrum is the fluorescence intensity. ; S404.2, Determination of fluorescence peak position: The wavelength corresponding to the maximum fluorescence intensity in the fluorescence spectrum is determined by analyzing the fluorescence spectrum, automatically identifying and manually calibrating the fluorescence peak position; S404.3, Calculation of Fluorescence Lifetime: Fluorescence Lifetime The physical quantity that describes the time required for a fluorescent molecule to return from an excited state to a ground state is estimated by combining the decay characteristics of the fluorescence intensity, that is, the fluorescence intensity changes with time. The formula for attenuation is: , It's time The fluorescence intensity at is the initial fluorescence intensity, that is, the fluorescence intensity at t=0, for a fixed response time of the instrument during the measurement process During this time, the fluorescence intensity changes from Decay to , then the fluorescence lifetime estimation formula is .

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