Method and device for detecting water temperature and organic matters in water

Abstract

The invention provides a detection method and a detection device for water temperature and organic matters in water, trace organic matters in a flowing water body are detected based on the change of an up-conversion luminescence peak intensity ratio corresponding to a first characteristic peak and a second characteristic peak in an up-conversion luminescence spectrum of sodium yttrium tetrafluoride particles (NaYF4: Yb, Tm), and the trace organic matters in the flowing water body are detected based on the change of the up-conversion luminescence peak intensity ratio corresponding to the first characteristic peak and the second characteristic peak in the up-conversion luminescence spectrum of the sodium yttrium tetrafluoride particles (NaYF4: Yb, Tm). The temperature change of the flowing water body is detected according to the change of the up-conversion luminescence peak intensity ratio corresponding to the third characteristic peak and the fourth characteristic peak in the up-conversion luminescence spectrum. The method can be used for efficiently detecting the organic matters in the water and detecting the temperature of the water body, has universality, is simple and quick, does not need to generate fluorescence by the target organic matters, and is wide in applicability.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical detection, and particularly relates to a method and a device for detecting water temperature and organic substances in water. Background Art

[0002] There are a very large number of types of organic substances. Currently, methods for detecting organic substances by fluorescence usually include fluorescence method, fluorescence quenching method, etc. However, these detection methods usually require designing specific fluorescent probes to achieve the detection of specific organic substances. Since there are thousands of types of organic substances, designing fluorescent probes for each type of organic substance would require a high cost. Moreover, due to different principles, the detection of organic substances and the detection of organic substances in water usually cannot share the same detection platform, resulting in a decrease in the generality of detection means. And when it is necessary to measure the water temperature, a special temperature sensor or thermometer is also required to achieve it. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a method and a device for detecting water temperature and organic substances in water, aiming to solve the problems of high cost in detecting organic substances in water and the need to use other special temperature detection devices to collect temperature in related technologies.

[0004] To solve the above technical problem, the present invention is implemented as follows. On the one hand, a method for detecting water temperature and organic substances in water is provided, including the following steps:

[0005] S1. Uniformly disperse rare-earth-doped sodium yttrium tetrafluoride particles (NaYF4:Yb,Tm) on a polydimethylsiloxane (PDMS) substrate containing silica powder. The sodium yttrium tetrafluoride particles are fixed on the surface of the PDMS to obtain a PDMS detection block.

[0006] S2. Place the detection block in the flowing water sample to be measured, use a near-infrared laser to excite the sodium yttrium tetrafluoride particles to generate upconversion luminescence, and obtain the corresponding upconversion luminescence spectrum.

[0007] S3. Based on the upconversion luminescence spectrum, calculate the first intensity ratio of the first characteristic peak and the second characteristic peak of the sodium yttrium tetrafluoride particles in the water sample to be measured, and the second intensity ratio of the third characteristic peak and the fourth characteristic peak of the sodium yttrium tetrafluoride particles in the water sample to be measured. Among them, the first characteristic peak and the second characteristic peak are characteristic peaks sensitive to the target organic substance, and the third characteristic peak and the fourth characteristic peak are characteristic peaks sensitive to temperature.

[0008] S4. Compare the first intensity ratio with the first preset intensity ratio to determine whether there is a target organic substance in the water sample to be measured. Among them, the first preset intensity ratio is the intensity ratio of the first characteristic peak and the second characteristic peak measured in an ideal water sample.

[0009] S5. Substitute the second intensity ratio into the preset linear relationship to calculate the temperature value of the water sample to be measured.

[0010] The organic substances in the solution of the present application can be tetrachloroethylene, tetrahydrofuran, ethyl acetate, oleic acid, cyclohexane, etc., which are not limited herein. An ideal water sample can refer to a water sample without organic substances; when there are organic substances in the water body, the contact between the organic substances and the sodium yttrium tetrafluoride doped with rare earths will affect the intensity ratio of relevant characteristic peaks, and different organic substances have different spectral response sensitivities; when the first intensity ratio is the same as the first preset intensity ratio, it indicates that there are no organic substances in the water sample to be measured, or the organic substances contained in the water sample to be measured are lower than the detection limit; when the first intensity ratio is different from the first preset intensity ratio, it indicates that there are target organic substances in the water sample to be measured. When the temperature of the water changes, it will affect the luminescence characteristics of the sodium yttrium tetrafluoride particles, thereby changing the intensity ratio of the corresponding luminescence peaks. Using this characteristic, the change in water temperature can be monitored. It can be seen that by using the property that the intensity of the luminescence peaks of different wavelengths of the upconversion luminescent particles will change due to the chemical substances in contact with the particles, the detection of organic substances in water is carried out without designing a special fluorescence probe for organic substances, which is beneficial to reducing costs; at the same time, the property that the intensity of the luminescence peaks of different wavelengths of the upconversion luminescent particles will change due to the change in the water temperature in contact with the particles can also be used to detect the water temperature, and the water temperature of the water body can be easily obtained without setting an additional thermometer or temperature sensor device.

[0011] Preferably, after step S4, it further includes:

[0012] When it is determined that there are target organic substances in the water sample to be measured, based on the relative magnitude of the first intensity ratio and the first preset intensity ratio, calculate the content of the organic substances in the water sample to be measured. That is, the intensity ratio of the first characteristic peak to the second characteristic peak will change linearly with the change in the content of the target organic substance in the water. Therefore, calibration can be carried out in advance for the target organic substance to determine the intensity ratio of the first characteristic peak to the second characteristic peak under different amounts of each target organic substance, and then the content of the target organic substance in the water sample to be measured can be determined according to the corresponding relationship between the actually measured luminescence intensity ratio and the calibrated intensity ratio.

[0013] Preferably, the sodium yttrium tetrafluoride particles are doped with 15% - 40% of Yb and 0.3% - 3% of Tm.

[0014] Preferably, the wavelength of the near-infrared laser is 980 nm. Using near-infrared light excitation and the detection wavelength being ultraviolet light, the fluorescence background is low.

[0015] Preferably, the emission wavelengths of the first characteristic peak and the second characteristic peak are 344 nm and 360 nm respectively.

[0016] Preferably, the first preset intensity ratio is 1:1.

[0017] Preferably, the emission wavelengths of the third characteristic peak and the fourth characteristic peak are 450 nm and 476 nm, respectively.

[0018] Preferably, the particle size of the sodium yttrium tetrafluoride particles is 1 - 10 μm.

[0019] Under the doping conditions and excitation conditions of the above sodium yttrium tetrafluoride particles, the present application selects the intensity values of the above characteristic peaks for detection and judgment. The characteristic peaks are significant and stable, which is more conducive to accurately obtaining the content of organic matter in water and the water temperature.

[0020] Preferably, step S1 includes:

[0021] Take 0.05 - 0.12 g of rare earth - doped sodium yttrium tetrafluoride particles and add them to 5 - 10 mL of ethanol solution to obtain a turbid solution.

[0022] Transfer the turbid solution onto a quartz wafer and evaporate the ethanol to obtain a quartz wafer with sodium yttrium tetrafluoride particles dispersed on its surface.

[0023] Mix 10 - 15 g of polydimethylsiloxane with 2 - 2.5 g of SiO2, and transfer the obtained mixture onto the quartz wafer with sodium yttrium tetrafluoride particles dispersed on its surface, and cure it to obtain a combined block.

[0024] Demold the combined block to obtain a detection block.

[0025] Exemplarily, the steps for preparing the detection block in the present application can be carried out as follows:

[0026] Take 0.05 - 0.1 g of rare earth - doped sodium yttrium tetrafluoride particles, add them to 5 - 10 mL of anhydrous ethanol and stir to obtain a turbid solution containing sodium yttrium tetrafluoride particles.

[0027] Use a pipette to take 60 - 80 μL of the turbid solution and drop it onto the quartz wafer, and wait for the ethanol to evaporate completely.

[0028] Repeat the above operation 10 - 15 times to prepare a quartz wafer with doped sodium yttrium tetrafluoride particles dispersed on its surface.

[0029] Take 11 - 13 g of PDMS in total, add 2 - 2.5 g of SiO2 powder to it, stir evenly, put it into a vacuum chamber to remove air bubbles, and then pour it onto the quartz wafer with doped sodium yttrium tetrafluoride particles dispersed on its surface, and wait for it to cure to obtain a combined block.

[0030] Demold the combined block, that is, remove the quartz wafer, to obtain a PDMS detection block for detection.

[0031] Exemplarily, in some embodiments, it may further include the process of preparing sodium yttrium tetrafluoride particles. The preparation method of the sodium yttrium tetrafluoride particles may include the following steps:

[0032] Y(NO3)3·6H2O, Yb(NO3)3·5H2O, and Tm(NO3)3·5H2O were added to deionized water in a weight ratio of 1:(0.2 - 0.6):(0.005 - 0.045) to prepare a 0.5 mol / L Ln(NO3)3 (Ln = Y, Yb, Tm) solution.

[0033] The above solution was added to a 0.025 mol / L aqueous solution of ethylenediaminetetraacetic acid in a volume ratio of 1:(10 - 50) and continuously stirred for 60 min.

[0034] A 0.5 mol / L NaF solution was added to the stirred solution in a volume ratio of Ln(NO3)3 (Ln = Y, Yb, Tm) solution to NaF solution of 1:16 and stirring was continued for 60 min.

[0035] The stirred solution was poured into a high-pressure reactor and reacted at 150 - 200 °C for 16 - 20 h.

[0036] The particles obtained after the reaction were rinsed with a mixed solution of ethanol and water in a volume ratio of 1:1, and then centrifuged at a speed of 10000 rpm for 5 min to obtain sodium yttrium tetrafluoride NaYF4:(15% - 40%)Yb, (0.3% - 3%)Tm particles with a size of 1 - 10 microns.

[0037] On the other hand, a detection device for water temperature and organic matter in water is provided to implement the detection method described in the above first aspect. The detection device includes: a sample carrier device, a laser, and a spectrometer; the sample carrier device is used to carry the water sample to be measured and the detection block, and to make the water sample flow; the laser is used to emit laser light to the detection block to excite the sodium yttrium tetrafluoride particles to generate upconversion luminescence; the spectrometer is used to obtain the upconversion light and generate a corresponding upconversion luminescence spectrum.

[0038] Compared with the prior art, the detection method and detection device for water temperature and organic matter in water of the present invention have the beneficial effects that: while detecting organic matter in water by using upconversion luminescent particles, the water temperature can also be detected. Since different types of organic matter can change the peak ratio of upconversion luminescence, the organic matter detection method provided in this application has universality and can be used to detect various organic matters. And the detection process does not require the organic matter to be detected to generate fluorescence, so the applicability is wide. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 is a schematic diagram of the overall structure of the detection device for water temperature and organic matter in water in an embodiment of the present invention;

[0040] Figure 2is the upconversion spectrum of the solution of no organic matter and a small amount of tetrachloroethylene in water in the embodiment of the present invention;

[0041] Figure 3 is the upconversion spectrum of the water body at 29.9 °C, 34.2 °C and 44.5 °C in the embodiment of the present invention;

[0042] Figure 4 is the relationship diagram between the tetrachloroethylene content and the fluorescence intensity ratio in the embodiment of the present invention;

[0043] Figure 5 is the relationship diagram between the temperature and the fluorescence intensity ratio in the embodiment of the present invention;

[0044] Figure 6 is the upconversion spectrum of the solution of no organic matter and a small amount of tetrahydrofuran in water in the embodiment of the present invention;

[0045] Figure 7 is the upconversion spectrum of the water body at 30.4 °C, 36.7 °C and 48.0 °C in the embodiment of the present invention;

[0046] Figure 8 is the relationship diagram between the tetrahydrofuran content and the fluorescence intensity ratio in the embodiment of the present invention;

[0047] Figure 9 is the upconversion spectrum of the solution of no organic matter and a small amount of ethyl acetate in water in the embodiment of the present invention;

[0048] Figure 10 is the upconversion spectrum of the water body at 28.9 °C, 39.3 °C and 48.5 °C in the embodiment of the present invention;

[0049] Figure 11 is the relationship diagram between the ethyl acetate content and the fluorescence intensity ratio in the embodiment of the present invention;

[0050] Figure 12 is the upconversion spectrum of the solution of no organic matter and a small amount of oleic acid in water in the embodiment of the present invention;

[0051] Figure 13 is the upconversion spectrum of the water body at 30.1 °C, 41.6 °C and 47.6 °C in the embodiment of the present invention;

[0052] Figure 14 is the relationship diagram between the oleic acid content and the fluorescence intensity ratio in the embodiment of the present invention;

[0053] Figure 15 is the upconversion spectrum of the solution of no organic matter and a small amount of cyclohexane in water in the embodiment of the present invention;

[0054] Figure 16They are the upconversion spectra of the water body at 26.0 °C, 37.1 °C, and 42.0 °C in the embodiments of the present invention.

[0055] Figure 17 It is a relationship diagram between the cyclohexane content and the fluorescence intensity ratio in the embodiments of the present invention. Detailed implementation manners

[0056] In order to make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0057] In this embodiment, the water temperature and water organic matter detection device is used to implement the water temperature and water organic matter detection method. As Figure 1 shown, the detection device includes a sample carrier device, a laser, and a spectrometer; the sample carrier device is used to carry the water sample to be measured and the detection block, and to make the water sample flow; the laser is used to emit laser light to the detection block to excite the sodium yttrium tetrafluoride particles to generate upconversion luminescence; the spectrometer is used to obtain the upconversion light and generate the corresponding upconversion luminescence spectrum.

[0058] Specifically, the sample carrier device includes a main body portion formed with a flow channel and a driving device installed in the flow channel. The flow channel can allow the water sample to be measured to flow, and when the driving device works, it can drive the water sample to be measured to flow in the flow channel. When it is necessary to detect the temperature and organic matter content of the water sample to be measured, the PDMS detection block can be placed in the flow channel, and then the laser can be used to emit 980 nm laser light to the detection block to excite the sodium yttrium tetrafluoride particles on this PDMS detection block to generate upconversion luminescence. This upconversion luminescence can be connected to spectrometer 1 and spectrometer 2 respectively through a Y-shaped optical fiber. Spectrometer 1 can be used to detect two emission peaks at 344 nm and 360 nm, and spectrometer 2 can be used to detect two emission peaks at 450 nm and 476 nm; then the first intensity ratio and the second intensity ratio can be calculated respectively, and the content of the target organic matter in the water sample to be measured can be calculated according to the first intensity ratio, and the temperature of the water sample to be measured can be calculated according to the second intensity ratio. It can be understood that in some other implementation manners, only the same spectrometer can also be used to detect these emission peaks at 344 nm, 360 nm, 450 nm, and 476 nm, which is not limited herein.

[0059] Based on the above experimental equipment foundation, the following embodiments are provided in this application.

[0060] Embodiment of the preparation of the detection block:

[0061] Y(NO3)3·6H2O, Yb(NO3)3·5H2O and Tm(NO3)3·5H2O were added to deionized water according to the weight ratio of 1:0.3:0.015 to prepare a 0.5 mol / L Ln(NO3)3 (Ln = Y, Yb, Tm) solution;

[0062] The above solution was added to a 0.025 mol / L aqueous solution of ethylenediaminetetraacetic acid according to the volume ratio of 1:20 and continuously stirred for 1 hour;

[0063] A 0.5 mol / L NaF solution was added to the stirred solution according to the volume ratio of Ln(NO3)3 (Ln = Y, Yb, Tm) solution to NaF solution of 1:16 and stirring was continued for 1 hour;

[0064] The above stirred solution was poured into a high-pressure reactor and reacted at 180 °C for 18 hours;

[0065] The particles obtained after the reaction were rinsed with a mixed solution of ethanol and water in a volume ratio of 1:1 and then centrifuged at 10,000 rpm for 10 minutes to obtain sodium yttrium tetrafluoride (NaYF4: 20% Yb, 1% Tm) particles with a size between 3 and 8 microns;

[0066] 0.1 g of sodium yttrium tetrafluoride (NaYF4: 20% Yb, 1% Tm) particles were taken and added to 10 mL of absolute ethanol and continuously stirred to obtain a turbid solution containing sodium yttrium tetrafluoride (NaYF4: 20% Yb, 1% Tm) particles. 70 μL of the turbid solution was taken with a pipette and dropped onto a quartz plate, and waited for the ethanol in it to evaporate completely. The steps were repeated 12 times to prepare a quartz plate with surface-dispersed doped sodium yttrium tetrafluoride particles;

[0067] 13.2 g of PDMS in total weight was taken, 2.5 g of SiO2 powder was added thereto, and after stirring evenly, it was put into a vacuum box to remove air bubbles, and then poured onto the quartz plate with surface-dispersed doped sodium yttrium tetrafluoride particles, and after waiting for it to cure, it was demolded to obtain a PDMS test block for detection.

[0068] Example 1 of organic matter detection and temperature detection:

[0069] The above PDMS test block containing sodium yttrium tetrafluoride particles was placed in the device as Figure 1 shown.

[0070] The sodium yttrium tetrafluoride particles on this PDMS block were excited with a 980 nm laser, and the upconversion luminescence spectrum was detected. The upconversion luminescence spectrum contains multiple luminescence peaks. The intensity ratio of the two luminescence peaks with peak positions at 344 nm and 360 nm in the spectrum calculated in Spectrometer 1 (as Figure 2 shown) is 1:1. Based on the detection spectrum of Spectrometer 2 (as Figure 3When the detection block is in the water flow at 29.9 °C, the intensity ratio of the two emission peaks with peaks at 450 nm and 476 nm is calculated to be 1:0.658.

[0071] Add tetrachloroethylene with a volume ratio of 0.77‰ to the water and heat the water flow. Then, obtain the up-conversion luminescence spectrum again (as Figure 2 shown). Calculate the intensity ratio of the two emission peaks at 344 nm and 360 nm to be 0.93:1. When tetrachloroethylene is the detection target, there is a linear change between the content of tetrachloroethylene and the corresponding first intensity ratio. As Figure 4 shown is the corresponding change curve. Combining this change curve and the above measurement data, it can be seen that using the method provided in this application to detect the content of tetrachloroethylene in water has high accuracy.

[0072] When the water sample to be measured is heated to 34.2 °C, calculate the intensity ratio of the two emission peaks with peaks at 450 nm and 476 nm in the spectrum (as Figure 3 shown) to be 1:0.664. When heated to 44.5 °C, calculate the intensity ratio of the two emission peaks with peaks at 450 nm and 476 nm in the spectrum (as Figure 3 shown) to be 1:0.689. As Figure 5 shown is the relationship diagram of temperature versus the second intensity ratio. It can be seen that the above measurement data of the emission peak intensities at different temperatures all satisfy the linear change relationship in this relationship diagram.

[0073] Example 2 of organic matter detection and temperature detection:

[0074] Put the above PDMS detection block containing sodium yttrium tetrafluoride particles into the device as Figure 1 shown.

[0075] Use a 980 nm laser to excite the sodium yttrium tetrafluoride particles on this PDMS block to obtain the corresponding up-conversion luminescence spectrum, and its up-conversion luminescence spectrum contains multiple emission peaks. Calculate the intensity ratio of the two emission peaks with peaks at 344 nm and 360 nm in the spectrum (as Figure 6 shown) in the spectrometer 1 to be 1:1. Based on the detection spectrum of the spectrometer 2 (as Figure 7 shown), calculate the intensity ratio of the two emission peaks with peaks at 450 nm and 476 nm when the detection block is in the water flow at 30.4 °C to be 1:0.646.

[0076] Add tetrahydrofuran with a volume ratio of 0.88‰ to the water and heat the water flow. Then, obtain the up-conversion luminescence spectrum again, as Figure 6 shown. Calculate the intensity ratio of the two emission peaks at 344 nm and 360 nm to be 0.96:1. When tetrahydrofuran is the detection target, there is a linear change between the content of tetrahydrofuran and the corresponding first intensity ratio. As Figure 8The corresponding change curve is shown. Combining this change curve with the above measurement data, it can be seen that the method provided by the present application for detecting the content of tetrahydrofuran in water has high accuracy.

[0077] Heat the water sample to be measured to 36.7 °C and calculate the spectrum again (as Figure 7 shown), the intensity ratio of the two emission peaks with peaks at 450 nm and 476 nm in the spectrum is 1:0.654. Heat to 48 °C and calculate the spectrum (as Figure 7 shown), the intensity ratio of the two emission peaks with peaks at 450 nm and 476 nm in the spectrum is 1:0.692. It can be seen that the above detection results also satisfy the linear change relationship as Figure 5 shown.

[0078] Example 3 of organic matter detection and temperature detection:

[0079] Put the above PDMS detection block containing sodium yttrium tetrafluoride particles into the device as Figure 1 shown.

[0080] Use a 980 nm laser to excite the sodium yttrium tetrafluoride particles on this PDMS block to obtain the corresponding up-conversion luminescence spectrum, and its up-conversion luminescence spectrum contains multiple emission peaks. Calculate the intensity ratio of the two emission peaks with peaks at 344 nm and 360 nm in the spectrum (as Figure 9 shown) in spectrometer 1 is 1:1. Based on the detection spectrum of spectrometer 2 (as Figure 10 shown), calculate the intensity ratio of the two emission peaks with peaks at 450 nm and 476 nm when the detection block is in the water flow at 28.9 °C is 1:0.645.

[0081] Add ethyl acetate with a volume ratio of 0.71‰ to the water and heat the water flow, and obtain the up-conversion luminescence spectrum again. Calculate the intensity ratio of the two emission peaks at 344 nm and 360 nm is 0.95:1. When ethyl acetate is used as the detection target, there is a linear change between the content of ethyl acetate and the corresponding first intensity ratio, as Figure 11 shown. Combining this change curve with the above measurement data, it can be seen that the method provided by the present application for detecting the content of ethyl acetate in water has high accuracy.

[0082] Heat the water sample to be measured to 39.3 °C and calculate the spectrum again (as Figure 10 shown), the intensity ratio of the two emission peaks with peaks at 450 nm and 476 nm in the spectrum is 1:0.657. Heat to 48.5 °C and calculate the spectrum (as Figure 10 shown), the intensity ratio of the two emission peaks with peaks at 450 nm and 476 nm in the spectrum is 1:0.685. It can be seen that the above detection results also satisfy the linear change relationship as Figure 5 shown.

[0083] Example 4 of organic matter detection and temperature detection:

[0084] Put the above PDMS detection block containing sodium yttrium tetrafluoride particles into the device as Figure 1 shown.

[0085] Use a 980 nm laser to excite the sodium yttrium tetrafluoride particles on this PDMS block to obtain the corresponding up-conversion luminescence spectrum, and its up-conversion luminescence spectrum contains multiple luminescence peaks. Calculate the intensity ratio of the two luminescence peaks with peaks at 344 nm and 360 nm in the spectrometer 1 (as Figure 12 shown) to be 1:1. Based on the detection spectrum of spectrometer 2 (as Figure 13 shown), calculate the intensity ratio of the two luminescence peaks with peaks at 450 nm and 476 nm when the detection block is in the water flow at 30.1 °C to be 1:0.665.

[0086] Add oleic acid with a volume ratio of 0.43‰ to the water and heat the water flow, and obtain the up-conversion luminescence spectrum again. As Figure 12 shown, calculate the intensity ratio of the two luminescence peaks at 344 nm and 360 nm to be 0.94:1; when oleic acid is used as the detection target, there is a linear change between the content of oleic acid and the corresponding first intensity ratio. As Figure 14 shown is the corresponding change curve. Combining this change curve and the above measurement data, it can be seen that the method provided by this application has high accuracy in detecting the content of oleic acid in water.

[0087] Heat the water sample to be measured to 41.6 °C and calculate the intensity ratio of the two luminescence peaks with peaks at 450 nm and 476 nm in the spectrum again (as Figure 14 shown) to be 1:0.686. Heat it to 47.6 °C and calculate the intensity ratio of the two luminescence peaks with peaks at 450 nm and 476 nm in the spectrum (as Figure 14 shown) to be 1:0.705. It can be seen that the above detection results also satisfy the linear change relationship as Figure 5 shown.

[0088] Example 5 of organic matter detection and temperature detection:

[0089] Put the above PDMS detection block containing sodium yttrium tetrafluoride particles into the device as Figure 1 shown.

[0090] Use a 980 nm laser to excite the sodium yttrium tetrafluoride particles on this PDMS block to obtain the corresponding up-conversion luminescence spectrum, and its up-conversion luminescence spectrum contains multiple luminescence peaks. Calculate the spectrum in spectrometer 1 (as Figure 15In the figure shown, the intensity ratio of the two emission peaks with peaks at 344 nm and 360 nm is 1:1. Based on the detection spectrum of the spectrometer 2 (as Figure 16 shown), when the detection block is in the water flow at 26.0 °C, the intensity ratio of the two emission peaks with peaks at 450 nm and 476 nm is 1:0.651.

[0091] Cyclohexane with a volume ratio of 0.5‰ is added to the water and the water flow is heated. The up-conversion luminescence spectrum is obtained again, and the intensity ratio of the two emission peaks at 344 nm and 360 nm is calculated to be 0.95:1; when cyclohexane is the detection target, there is a linear change between the content of cyclohexane and the corresponding first intensity ratio, as Figure 17 shown in the corresponding change curve. Combining this change curve and the above measurement data, it can be seen that the method provided by this application for detecting the content of cyclohexane in water has high accuracy.

[0092] The water sample to be tested is heated to 37.1 °C and the spectrum is calculated again (as Figure 16 shown), and the intensity ratio of the two emission peaks with peaks at 450 nm and 476 nm is 1:0.673. When heated to 42.0 °C, the intensity ratio of the two emission peaks with peaks at 450 nm and 476 nm in the calculated spectrum (as Figure 16 shown) is 1:0.68. It can be seen that the above detection results also satisfy the linear change relationship as Figure 5 shown.

[0093] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for detecting water temperature and organic matter in water, characterized in that: The following steps are involved: S1, uniformly dispersing rare earth-doped sodium yttrium tetrafluoride particles on a polydimethylsiloxane substrate containing silicon dioxide powder to obtain a detection block; S2, placing the detection block in a flowing water sample to be tested, using a near-infrared laser to excite the sodium yttrium tetrafluoride particles, and obtaining a corresponding up-conversion luminescence spectrum; S3. Based on the up-conversion luminescence spectrum, calculate a first intensity ratio of a first characteristic peak to a second characteristic peak of the sodium yttrium tetrafluoride particles in the water sample to be tested, and a second intensity ratio of a third characteristic peak to a fourth characteristic peak of the sodium yttrium tetrafluoride particles in the water sample to be tested; wherein the first characteristic peak and the second characteristic peak are characteristic peaks sensitive to target organic matter, and the third characteristic peak and the fourth characteristic peak are characteristic peaks sensitive to temperature; S4, comparing the first intensity ratio with a first preset intensity ratio to determine whether the target organic matter exists in the water sample to be tested; wherein the first preset intensity ratio is an intensity ratio of the first characteristic peak to the second characteristic peak measured in an ideal water sample; S5. Substitute the second intensity ratio into a preset linear relationship to calculate the temperature value of the water sample to be tested.

2. The method for detecting water temperature and organic matter in water according to claim 1, characterized in that: After step S4, the method further includes: When it is determined that the target organic matter exists in the water sample to be tested, the content of the organic matter in the water sample to be tested is calculated based on the relative size of the first intensity ratio and the first preset intensity ratio.

3. The method for detecting water temperature and organic matter in water according to claim 2, characterized in that: The emission wavelengths of the first characteristic peak and the second characteristic peak are 344 nm and 360 nm respectively.

4. The method for detecting water temperature and organic matter in water according to claim 3, characterized in that: The first preset intensity ratio is 1:

1.

5. The method for detecting water temperature and organic matter in water according to claim 1, characterized in that: The emission wavelengths of the third characteristic peak and the fourth characteristic peak are 450 nm and 476 nm respectively.

6. The method for detecting water temperature and organic matter in water according to claim 1, characterized in that: The step S1 comprises: 0.05-0.12 g of rare earth-doped sodium yttrium tetrafluoride particles were added to 5-10 mL of ethanol solution to obtain a turbid solution; Transferring the turbid solution to a quartz plate and evaporating the ethanol to obtain a quartz plate with the sodium yttrium tetrafluoride particles dispersed on the surface; Mixing 10-15 g of polydimethylsiloxane with 2-2.5 g of SiO2, and transferring the obtained mixture to the quartz sheet with the sodium yttrium tetrafluoride particles dispersed on the surface, and solidifying the mixture to obtain a composite block; The assembly block is demoulded to obtain the detection block.

7. The method for detecting water temperature and organic matter in water according to claim 1, characterized in that: The sodium yttrium tetrafluoride particles are doped with 15% to 40% of Yb and 0.3% to 3% of Tm.

8. The method for detecting water temperature and organic matter in water according to claim 7, characterized in that: The particle size of the sodium yttrium tetrafluoride particles is 1 to 10 μm.

9. The method for detecting water temperature and organic matter in water according to claim 1, characterized in that: The wavelength of the near-infrared laser is 980 nm.

10. A device for detecting water temperature and organic matter in water, used to implement the detection method according to any one of claims 1 to 9, characterized in that: The detection device includes a sample carrier, a laser and a spectrometer; the sample carrier is used to carry the water sample to be tested and the detection block, and to make the water sample flow; the laser is used to emit laser light to the detection block to excite the sodium yttrium tetrafluoride particles to produce up-conversion luminescence; the spectrometer is used to obtain the up-conversion light and generate a corresponding up-conversion luminescence spectrum.

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