Pollutant source monitoring and analyzing method in hydraulic lubricating system

Abstract

The invention discloses a method for monitoring and analyzing a pollutant source in a hydraulic lubricating system, and relates to the technical field of hydraulic lubricating system monitoring, the method for monitoring and analyzing the pollutant source comprises the following steps: S100, preparation of a quantum dot fluorescent probe: designing and synthesizing the quantum dot fluorescent probe aiming at oxidation pollutants in the hydraulic lubricating system, by means of surface modification and ligand selection of quantum dots, the quantum dots can be specifically combined with target pollutants and generate remarkable fluorescence change, the specific quantum dot fluorescent probe for oxidation pollutants in a hydraulic lubricating system is designed and synthesized, accurate detection of micro pollutants in oil is achieved, and the detection sensitivity is high. According to the present invention, the quantum dot fluorescence probe can specifically bind to the target pollutant through the surface functional modification so as to produce the significant fluorescence change, such that the detection accuracy is improved.

Description

Technical Field

[0001] The 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 automotive industries. They can reduce friction, reduce wear, transmit power, and ensure the stable operation of equipment. However, various pollutants are inevitably generated during the operation of the system. The presence of these pollutants poses a serious threat to the performance, reliability, and life of the system.

[0003] At present, the monitoring of pollutants in hydraulic lubrication systems mainly relies on physical filtration and chemical analysis methods. Although physical filtration can remove larger particles of pollutants, it is powerless to detect trace harmful compounds. Although chemical analysis methods can provide detailed information on pollutants, they usually require complex sample pretreatment, professional operators and expensive analysis equipment, and the analysis cycle is long, which cannot meet the needs of real-time monitoring. In particular, for the detection of trace pollutants such as oxidation products, the existing technology lacks 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 needs 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 prior art 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 quantum dot fluorescent probes with specific responsiveness, and further analyze the sources of 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 for oxidative pollutants in hydraulic lubrication systems. Through surface modification and ligand selection of quantum dots, they can specifically bind to target pollutants and produce significant fluorescence changes;

[0008] S200, probe introduction and distribution: introduce the prepared quantum dot fluorescent probe 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 virtue of the flow and stirring of the oil;

[0009] S300, establish an accurate quantitative relationship model: prepare target pollutant oil samples with known concentrations, add quantum dot fluorescent probes for detection, obtain fluorescence signal change data, and establish a quantitative relationship equation between fluorescence signal changes and pollutant concentrations 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, and judging the presence of the target pollutant by measuring the change in fluorescence intensity. At the same time, the concentration of the pollutant is evaluated according to 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 in different parts, 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 having a particle size and luminescence properties through chemical synthesis;

[0014] S102, chemical synthesis of quantum dots: using hot injection method, by precisely controlling the reaction temperature, reaction time and precursor concentration conditions, the particle size distribution of quantum dots is uniform and the morphology is regular. By adjusting the reaction solvent and surfactant, the surface state of quantum dots is further optimized;

[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 quantum dot fluorescent probes with specific responses.

[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 surface of quantum dots 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 quantum dots, namely fluorescence quenching and enhancement, are analyzed, thereby specifically detecting oxidized pollutants.

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

[0018] S102.1, reaction conditions are set: under inert gas protection, quantum dots are synthesized by hot injection method, wherein the reaction temperature is 200° C. to 300° C., the reaction time is 2 hours to 5 hours, and the precursor concentration is 0.01 M to 0.1 M;

[0019] S102.2, selection of reaction solvent and surfactant: use a mixed solvent of trioctyl phosphine oxide (TOPO) and a selenium source, in which 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: using a microinjector, the probe solution is injected into the oil circulation of the hydraulic lubrication system, and the injection speed is controlled at 0.1 to 1 ml / min. At the same time, it is ensured that the injection volume will not have a significant impact on 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, with a concentration range covering the concentrations of pollutants present in the oil to be tested;

[0027] S302, adding and mixing probes: adding an equal amount of quantum dot fluorescent probes to each standard solution, and mixing the probes and target pollutants thoroughly and evenly by stirring and shaking;

[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, and paying special attention to the change of 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, establishing 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 S305 collects data of standard solutions of different concentrations, and 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 concentration of the pollutant from the change in fluorescence intensity. The specific steps are:

[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] Construction of quantitative relationship model: 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, F = aC + b, where a is the slope, indicating 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 labeled sample data is (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 centrifugation, to remove large particle impurities that interfere with fluorescence detection;

[0040] S403, mixing reaction and fluorescence detection: fully mix the quantum dot fluorescent probe and the oil sample by stirring and shaking, use a fluorescence spectrophotometer to perform fluorescence detection on the mixed sample, record the fluorescence spectrum, and pay special attention to the change of fluorescence intensity;

[0041] S404, data analysis: analyzing the fluorescence spectrum to analyze the change of the fluorescence signal, including the measurement of fluorescence intensity, the determination of fluorescence peak position and the calculation of fluorescence lifetime;

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

[0043] Furthermore, in the data analysis process of S404, the steps of calculating the measurement of fluorescence intensity, determination of fluorescence peak position and 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, where 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, automatic identification and manual calibration of fluorescence peak position by analyzing the fluorescence spectrum;

[0046] S404.3, Calculation of fluorescence lifetime: The fluorescence lifetime τ is a physical quantity that describes the time required for a fluorescent molecule to return from an excited state to a ground state. It is estimated by combining the decay characteristics of the fluorescence intensity, that is, the formula for the decay of the fluorescence intensity with 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 of different monitoring points in the hydraulic lubrication system, namely, the oil tank, the oil pump inlet, the 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, and identify the areas and positions where the fluorescence signal is significantly enhanced;

[0050] S503, System structure and working principle analysis: Based on the structural layout of the hydraulic lubrication system, the oil flow path and the working principles of each component, analyze the relationship between the area where the fluorescence signal is significantly enhanced and the potential pollution sources in the system, namely, seal wear, oil oxidation reaction area, and external pollutant invasion points;

[0051] S504, inference of pollutant sources: infer the source of pollutants based on comprehensive analysis of the distribution characteristics of fluorescent signals, system structure and working principle;

[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 at the same time, 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 prior art, the 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 oxidized pollutants in hydraulic lubrication systems, and realizes accurate detection of trace pollutants in oil. Due to its unique quantum size effect and surface effect, the quantum dot fluorescent probe has extremely high fluorescence quantum yield and photostability, and can significantly enhance the detection sensitivity of target pollutants. In addition, through surface functional modification, the quantum dot fluorescent probe can specifically bind to the target pollutants to produce 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 the maintenance and maintenance of the system.

[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 by means 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 determined by measuring the change in fluorescence intensity, and its concentration is evaluated. More importantly, the source of the pollutant is inferred 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. 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, objectives and features of the present invention will be set forth 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 taught from the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order 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 prior art descriptions. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0058] Figure 1 The present invention is an operation 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 technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0061] Embodiment 1

[0062] A method for monitoring and analyzing the sources of pollutants in a hydraulic lubrication system. The 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, and through surface functionalization modification, quantum dots can 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 preparation stage (S100) is entered, and 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 surface of the quantum dots through ligand exchange, thereby optimizing its solubility and biocompatibility. Molecules that can specifically recognize 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, the prepared quantum dot fluorescent probe is dispersed in dimethylformamide solvent to prepare a probe solution of appropriate concentration, and 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., filter and centrifuge to remove large particle impurities that interfere with fluorescence detection, fully mix the quantum dot fluorescent probe and the oil sample by stirring and oscillating, use a fluorescence spectrophotometer to perform fluorescence detection on the mixed sample, record the fluorescence spectrum, and pay special attention to the change of fluorescence intensity, measure the fluorescence intensity, determine the fluorescence peak, calculate the fluorescence lifetime, analyze the fluorescence spectrum, including the measurement of fluorescence intensity, the determination of fluorescence peak and the calculation of fluorescence lifetime, compare the detected fluorescence data with the standard curve established in S300, judge the presence or absence of the target pollutant according to the change of fluorescence intensity, and evaluate its concentration.

[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 caused an increase in oxidation products. An inspection and maintenance plan is formulated, the oil pump is disassembled and inspected, the inference of the source of the pollutants is verified, and the worn seals are cleaned and replaced. Then, monitoring is carried out again, and the monitoring and analysis results are fed back to optimize the system's operation and maintenance strategies 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] Embodiment 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, in order to demonstrate how to use quantum dot fluorescent probes for quantitative analysis and detection of pollutants.

[0071] Use high-precision measuring instruments to accurately prepare a series of target pollutant oil samples with known concentrations. The concentration range covers the possible pollutant concentrations in the oil to be tested, for example, from 0.05ppm to 5ppm. Add an equal amount of quantum dot fluorescent probe to each standard solution, and mix it with the target pollutant thoroughly and evenly through stirring and oscillation. Use a fluorescence spectrophotometer to perform fluorescence detection on the mixed samples. During the detection process, record the fluorescence spectra of the samples at each concentration, pay special attention to the changes in fluorescence intensity, and obtain fluorescence intensity data F, and pollutant concentration data C. Perform preliminary statistical analysis on these data to understand the distribution characteristics of the data.

[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 Solving 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 pipelines, 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 particle impurities that interfered with fluorescence detection. The quantum dot fluorescent probes were fully mixed with the oil sample by stirring and oscillating. The mixed sample was subjected to fluorescence detection using a fluorescence spectrophotometer, and the fluorescence spectrum was recorded, with special attention paid to the change 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 calculated in combination with 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 meas , 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, and 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 embodiment demonstrates in detail the implementation process of steps S300 and S400. By establishing an accurate quantitative relationship model and performing specific detection of quantum dot fluorescent probes, real-time monitoring and accurate evaluation of pollutants in the hydraulic lubrication system are successfully achieved. This method not only improves the sensitivity and accuracy of pollutant monitoring, but also provides strong data support for system maintenance.

[0075] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered 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 for oxidative pollutants in hydraulic lubrication systems. Through surface modification and ligand selection of quantum dots, they can specifically bind to target pollutants and produce significant fluorescence changes; S200, probe introduction and distribution: introduce the prepared quantum dot fluorescent probe 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 virtue of the flow and stirring of the oil; S300, establish an accurate quantitative relationship model: prepare target pollutant oil samples with known concentrations, add quantum dot fluorescent probes for detection, obtain fluorescence signal change data, and establish a quantitative relationship equation between fluorescence signal changes and pollutant concentrations 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, and judging the presence of the target pollutant by measuring the change in fluorescence intensity. At the same time, the concentration of the pollutant is evaluated according to the degree of change in fluorescence intensity; S500, pollutant source tracing and analysis: Analyze the source of pollutants based on the changes in fluorescent signals detected in different parts, combined with the structure and working principle of the hydraulic lubrication system.

2. According to claim 1, a method for monitoring and analyzing the source of pollutants in a hydraulic lubrication system is 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 having a particle size and luminescence properties through chemical synthesis; S102, chemical synthesis of quantum dots: using hot injection method, by precisely controlling the reaction temperature, reaction time and precursor concentration conditions, the particle size distribution of quantum dots is uniform and the morphology is regular. By adjusting the reaction solvent and surfactant, the surface state of quantum dots is further optimized; 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 quantum dot fluorescent probes with specific responses.

3. According to claim 2, a method for monitoring and analyzing the source of pollutants in a hydraulic lubrication system is characterized in that: The S103 is to achieve specific recognition of oxidized pollutants by quantum dot fluorescent probes, and the surface of quantum dots is functionally modified. 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 surface of quantum dots 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, namely fluorescence quenching and enhancement, are analyzed to specifically detect oxidized pollutants.

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 S102 are: S102.1, reaction conditions are set: under inert gas protection, quantum dots are synthesized by hot injection method, wherein the reaction temperature is 200° C. to 300° C., the reaction time is 2 hours to 5 hours, and the precursor concentration is 0.01 M to 0.1 M; S102.2, selection of reaction solvent and surfactant: use a mixed solvent of trioctyl phosphine oxide (TOPO) and a selenium source, in which 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.

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 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: using a microinjector, the probe solution is injected into the oil circulation of the hydraulic lubrication system, and the injection speed is controlled at 0.1 to 1 ml / min. At the same time, it is ensured that the injection volume will not have a significant impact on 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.

6. 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, with a concentration range covering the concentrations of pollutants present in the oil to be tested; S302, adding and mixing probes: adding an equal amount of quantum dot fluorescent probes to each standard solution, and mixing the probes and target pollutants thoroughly and evenly by stirring and shaking; 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, and paying special attention to the change of 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, establishing 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.

7. The method for monitoring and analyzing the source of pollutants in a hydraulic lubrication system according to claim 1, characterized in that: The S305 collects standard solution data of different concentrations, and measures the fluorescence intensity change corresponding to each concentration, establishes a quantitative relationship model between the fluorescence signal and the pollutant concentration, and predicts the pollutant concentration from the fluorescence intensity change. The specific steps are: 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; Construction of quantitative relationship model: 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, F = aC + b, where a is the slope, indicating 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; Parameter estimation: Fluorescence detection is performed on the sample after S303 mixing, that is, the labeled sample data is (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, Parameter solution: solve the slope a and intercept b, that is 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 8. 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 centrifugation, to remove large particle impurities that interfere with fluorescence detection; S403, mixing reaction and fluorescence detection: fully mix the quantum dot fluorescent probe and the oil sample by stirring and shaking, use a fluorescence spectrophotometer to perform fluorescence detection on the mixed sample, record the fluorescence spectrum, and pay special attention to the change of fluorescence intensity; S404, data analysis: analyzing the fluorescence spectrum to analyze the change of the fluorescence signal, including the measurement of fluorescence intensity, the determination of fluorescence peak position and the calculation of fluorescence lifetime; S405, result comparison: compare the detected fluorescence data with the standard curve established in S300, determine the presence of the target pollutant based on the change in fluorescence intensity, and evaluate its concentration.

9. A method for monitoring and analyzing the source of pollutants in a hydraulic lubrication system according to claim 8, characterized in that: In the data analysis process of S404, the steps of calculating the measurement of fluorescence intensity, determination of fluorescence peak position and 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, where the maximum value of the fluorescence spectrum is the fluorescence intensity F max ; S404.2, determination of fluorescence peak position: the wavelength corresponding to the maximum fluorescence intensity in the fluorescence spectrum, automatic identification and manual calibration of fluorescence peak position by analyzing the fluorescence spectrum; S404.3, Calculation of fluorescence lifetime: The fluorescence lifetime τ is a physical quantity that describes the time required for a fluorescent molecule to return from an excited state to a ground state. It is estimated by combining the decay characteristics of the fluorescence intensity, that is, the formula for the decay of the fluorescence intensity with 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 F init Decay to F meas , then the fluorescence lifetime estimation formula is 10. 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 S500 are: S501, data collection and collation: collecting fluorescence detection data of different monitoring points in the hydraulic lubrication system, namely, the oil tank, the oil pump inlet, the 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, and identify the areas and positions where the fluorescence signal is significantly enhanced; S503, System structure and working principle analysis: Based on the structural layout of the hydraulic lubrication system, the oil flow path and the working principles of each component, analyze the relationship between the area where the fluorescence signal is significantly enhanced and the potential pollution sources in the system, namely, seal wear, oil oxidation reaction area, and external pollutant invasion points; S504, inference of pollutant sources: infer the source of pollutants based on comprehensive analysis of the distribution characteristics of fluorescent signals, system structure and working principle; 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 at the same time, provide feedback on the monitoring and analysis results to continuously optimize the operation and maintenance strategy of the hydraulic lubrication system.

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