129 results about "Fluorescence Spectrophotometry" patented technology

Aspects of the present disclosure include methods for spectrally resolving light from fluorophores in a sample. Methods according to certain embodiments include detecting light with a light detection system from a sample having a plurality of fluorophores having overlapping fluorescence spectra and spectrally resolving light from each fluorophore in the sample with a generalized least squares algorithm. In some embodiments, methods include estimating the abundance of one or more of the fluorophores in the sample, such as on a particle. In certain instances, methods include identifying the particle in the sample based on the abundance of each fluorophore and sorting the particle. Methods according to some embodiments includes spectrally resolving the light from each fluorophore by calculating a spectral unmixing matrix for the fluorescence spectra of each fluorophore. Systems and integrated circuit devices (e.g., a field programmable gate array) for practicing the subject methods are also provided.

Provided are a coal testing system and method, and a storage medium. The system comprises: a detection unit, which is used for collecting spectral data of a coal sample under test; a training unit, which is used for constructing, by means of the spectral data, neural networks across neural network dimensions on the basis of a greedy search, and obtaining a coal sample test model by means of performing training on the basis of simulated samples which have been subjected to sample augmentation; and an analysis unit, which is used for executing fusion processing on the spectral data to obtain target spectral data, and on the basis of the coal sample test model, executing target spectral data inference to obtain a coal test result, wherein the detection unit comprises a near-infrared spectroscopy collection module and an X-ray fluorescence spectroscopy collection module.

This invention discloses a method for determining fiber microplastics in aqueous textile solutions based on fluorescence spectrophotometry, belonging to the field of textile pollutant detection technology. The method includes: S1, collecting wastewater and filtering it through a filter membrane; S2, rinsing the filter membrane with sodium hypochlorite solution; S3, rinsing the fiber microplastics on the filter membrane into a separatory funnel; S4, pouring out a portion of the fiber microplastics from the upper end of the separatory funnel and collecting another portion from the lower end; S5, repeating S1-S4, rinsing the filter membrane with hydrochloric acid during this process, and collecting the remaining fiber microplastics; S6, dyeing the three solutions obtained; S7, preparing standard series solutions using polyester, polyamide, and polypropylene standard liner; S8, measuring and plotting a standard curve of fluorescence intensity versus fiber microplastic concentration using a fluorescence spectrophotometer; S9, measuring the fluorescence intensity of the three solutions obtained in S6. This invention is applicable to the field of aqueous textile solutions, enabling quantitative analysis of unknown samples, and can analyze both single and mixed samples with minimal detection bias.

The invention provides a sea surface oil film thickness measuring method based on optimized laser-induced fluorescence spectrum wave bands, and belongs to the technical field of spectral analysis. The method comprises the following steps: emitting an excitation light beam to a to-be-measured sea surface oil film by using a laser, and exciting the oil film to generate a fluorescence signal; receiving the fluorescence signal based on a spectrum acquisition device, and obtaining fluorescence spectrum data of the oil film; selecting a characteristic wave band from the fluorescence spectrum data through a sparse partial least square model, and predicting the thickness of the sea surface oil film based on the characteristic wave band in combination with Lasso regression; meanwhile, the selection of characteristic wave bands is optimized by using a hedera helix algorithm. According to the method, the characteristic wave band of oil film detection is selected through the sparse partial least square model, the oil film measurement characteristic wave band is efficiently and accurately obtained, full-wave band collection is avoided, and the detection efficiency is improved; and in combination with the hedera helix optimized sparse partial least square model, the accuracy of characteristic wave band selection and the generalization of the model are further improved, and the precision and efficiency of oil film thickness measurement are remarkably improved.

A digital-physical twin system and method for environmental process modeling and forecasting are disclosed. The system includes a digital twin server configured to receive environmental data from a real-world environment, including hyperspectral and spectroscopic imaging, simulate environmental process transitions using a predictive model based on the environmental data, and generate parameters for a physical experiment designed to validate or refine the predictive model. A physical twin device, comprising a scaled and instrumented representation of the real-world environment, is configured to execute the physical experiment under controlled conditions. Experimental data is returned to the digital twin to iteratively refine the predictive model in a closed-loop learning cycle using self-supervised and reinforcement learning. The system supports spatially-spectrally selective experimentation, including fluorescence spectroscopy, to enhance environmental sensing. This architecture enables scalable, sample-efficient modeling of processes such as post-wildfire hydrology, vegetation regrowth, and soil change.

The invention relates to a three-dimensional fluorescence spectrum image super-resolution reconstruction method for a water quality detection instrument, which is suitable for reconstructing a low-resolution and sparse three-dimensional fluorescence spectrum image collected by a portable water quality detection instrument into a high-resolution full spectrum. According to the method, an efficient super-resolution reconstruction network architecture composed of a feature extraction module, an up-sampling module and a trainable multi-Gaussian mixture point spread function is constructed. A joint loss function combining a reconstruction error and a degradation consistency error is designed, and a joint training strategy is adopted to synchronously optimize a network and PSF parameters, so that accurate reduction of a fluorescence peak shape structure and enhancement of spectrum authenticity are realized. The applicability and robustness of the portable water quality detection instrument based on the three-dimensional fluorescence spectrum in pollutant identification and analysis tasks are improved, and the portable water quality detection instrument is suitable for actual scenes such as intelligent water quality monitoring.

The invention relates to a gallium oxide defect detection method. The method comprises the following steps: step 1, obtaining exciting light with a proper wavelength; 2, modulating the exciting light obtained in the step 1 so as to enable the exciting light to accurately enter a microscope system with proper energy; 3, irradiating the modulated exciting light to a gallium oxide sample on an electric displacement table through a microscope system, collecting fluorescence generated after the gallium oxide sample is excited through the microscope system, and transmitting the fluorescence to a spectrograph system to obtain a corresponding fluorescence spectrogram under a preset single pixel point position; and 4, setting a spectrograph system to collect the fluorescence intensity under a specific wavelength, and driving the gallium oxide sample to move through an electric displacement table so as to scan the fluorescence intensity of all pixel point positions in a sample detection range, thereby obtaining a gallium oxide defect fluorescence intensity imaging graph in the sample detection range. The method has the advantage of high sensitivity, can realize rapid nondestructive detection, and also reduces the detection cost at the same time.

The invention provides an urban rainwater pipe network mixed connection tracing method based on a pollution source fluorescence spectrum library in combination with machine learning. The method relates to the fields of numerous pollution sources around a pipe network, complex mixing and connecting conditions and the like. The method comprises the following steps: sampling through an inspection well to obtain a water sample; extracting an organic matter multi-dimensional characteristic matrix from the water sample by adopting technologies such as three-dimensional fluorescence spectroscopy (EEM) and the like; and carrying out fluorescence data analysis on the multi-dimensional characteristic matrix by using an NPLSDA (N-Way Partial Least Squares Discriminant Analysis) model, carrying out comparative analysis and identification, and determining the source of the pollution source. According to the technology, the specific source of mixed connection sewage of the rainwater pipe network can be quickly diagnosed through mixed connection rainwater well sampling analysis, and efficient and convenient decision support is provided for mixed connection transformation and traceability investigation of the urban rainwater pipe network.

The invention discloses an iron ore composition detection method and system based on machine learning, and relates to the technical field of data processing.The method comprises the steps that iron ore feature information of target iron ore to be detected is collected, and a plurality of iron ore samples are collected; performing drying and grinding parameter optimization according to the iron ore characteristic information, drying and grinding the plurality of iron ore samples, and collecting the particle size and mass in each drying and grinding process to obtain a plurality of particle size sequence sets and a plurality of mass sequences; preparing a plurality of detection samples, and performing sample quality analysis according to the optimized drying and grinding parameters, the plurality of particle size sequence sets and the plurality of quality sequences to obtain a plurality of sample quality coefficients; and carrying out X-ray fluorescence spectrum detection on the plurality of detection samples to obtain a plurality of spectrum detection results, and carrying out component identification on the plurality of spectrum detection results according to the plurality of sample mass coefficients to obtain an iron ore component detection result. The technical problem of poor iron ore component detection accuracy in the prior art is solved.

The invention belongs to the field of soil dissolved organic matter analysis, and provides a multispectral-based DOM detection and reclamation influence evaluation method, which comprises the following steps: step 1, collecting dry farmland soil samples of different reclamation years, and obtaining soil column samples of a plough layer, a plow pan and subsoil; 2, extracting, centrifuging and filtering the soil sample to obtain a DOM solution; 3, detecting the DOM solution by adopting an ultraviolet-visible absorption spectrum; step 4, adopting a three-dimensional fluorescence spectrum and combining parallel factor analysis to obtain fluorescence components and source characteristics of the DOM solution; step 5, analyzing molecular composition and characteristic parameters of the DOM solution by adopting solid-phase extraction in combination with Fourier transform ion cyclotron resonance mass spectrometry; and step 6, based on the detection data in the steps 3-5, evaluating the influence of reclamation years on the composition, structure and degradation characteristics of the DOM. According to the method, multi-dimensional detection of soil DOM is realized through a multi-spectrum and mass spectrum combined technology, and DOM is comprehensively analyzed from a macrostructure to molecular composition.

Provided is a phosphor powder in which the balance of suitability, brightness, and excitation light blocking properties of a complex obtained from the phosphor powder with respect to a small-sized light-emitting device is improved. A phosphor powder containing SCASN phosphor particles, the phosphor powder having a volume-based median diameter (D50) of 0.1 [mu] m to 5.0 [mu] m (inclusive) as determined by a laser diffraction scattering method, and a peak wavelength of a fluorescence spectrum measured by a spectrophotometer when the phosphor powder is irradiated with light having a wavelength of 455 nm of 590.0 nm to 630.0 nm (inclusive), the absorption rate when the phosphor powder is irradiated with light having a wavelength of 455 nm is 80.0% or more.

The application discloses a kind of full-automatic high-throughput space-time resolution fluorescence spectrum imaging system and method, it is related to fluorescence signal spectrum field, including: workbench, sample stage, objective, for preloading sample stage with sample and placing it on workbench on mechanical arm sample inlet module, for laser beam to the output module of picosecond pulse laser of objective, for simultaneously collecting the spectral data and dynamic data of fluorescence signal generated after sample is focused by laser beam fluorescence signal detection module and control module;Sample stage and objective are sequentially spaced apart on workbench along the vertical direction from top to bottom;Mechanical arm sample inlet module, picosecond pulse laser output module and fluorescence signal detection module are respectively connected with control module communication.This application can realize the simultaneous acquisition of spectral data and dynamic data of fluorescence signal automatically.

This invention discloses a method for quantitative analysis of multiple components in oxidized slag based on X-ray fluorescence spectroscopy, belonging to the field of industrial process detection technology. The method includes: acquiring the raw energy spectrum data of a standard oxidized slag sample and the oxidized slag sample to be tested, and performing background subtraction and smoothing noise reduction; extracting the integral intensity of the characteristic peaks of target elements, establishing spectral interference correction relationships and matrix effect compensation relationships; establishing regression prediction models and residual compensation models for each target oxide based on the compensated characteristic intensities; inputting the characteristics of the sample to be tested into the models, and outputting the final predicted values ​​of each target oxide; improving the accuracy of feature information extraction in the multi-component system of oxidized slag, reducing errors caused by spectral overlap, excitation effects, and matrix effects, and improving the accuracy, result stability, and prediction consistency of quantitative analysis of multiple target oxides under different sample conditions, making it suitable for rapid detection and analysis of complex oxidized slag samples.

The invention discloses a sulfur-nitrogen co-doped carbon quantum dot modified polyaspartic acid derivative as well as a preparation method and application thereof. The derivative is prepared by taking citric acid and L-cysteine as precursors, synthesizing sulfur-nitrogen co-doped carbon quantum dots (SN-CDs) with rich functional groups on the surface by adopting a hydrothermal method, and introducing the sulfur-nitrogen co-doped carbon quantum dots into a side chain of polyaspartic acid (PASP) through graft copolymerization. The derivative not only retains the complexing ability of polyaspartic acid with metal ions such as calcium and magnesium, but also has excellent scale and corrosion inhibition performance; the optical characteristics of the carbon quantum dots are inherited, and stable fluorescence can be emitted under the excitation of specific wavelength, so that in-situ and real-time concentration monitoring in an industrial circulating cooling water system by utilizing a fluorescence spectrum technology is supported. The product does not contain phosphorus, is environment-friendly, conforms to the development trend of a green water treatment technology, and provides an innovative material solution for intelligent monitoring and fine management of a circulating water system while improving the comprehensive performance of scale and corrosion inhibition.

The present invention relates to methods for the fluorescence spectroscopic determination of the lignin content of cellulose samples, in which the lignin content is determined either by comparing the fluorescence emission spectrum of the sample with a reference sample or via the fluorescence decay spectrum. The present invention further relates to methods for the delignification of lignocellulose, particularly in the form of wood, in which such methods are used to monitor the progress of delignification, in particular to methods in which cellulose and lignin from the lignocellulose are separated from one another by extraction with an ionic liquid.

The invention discloses a method for simulating phosphorus and chromium migration during farmland irrigation with acid mine wastewater, which comprises the following steps: mixing a plant-derived organic material with deionized water to obtain a soluble organic matter; h2O2 oxidizes Fe < 2 + > to prepare pure Schwertmannite, and the pure Schwertmannite is placed in a phosphate solution to obtain phosphorus-loaded Schwertmannite; mixing the phosphorus-loaded Schwertmannite and the soluble organic matter with a chromate solution, carrying out oscillation adsorption, carrying out solid-liquid separation after adsorption, carrying out CrO and POconcentration change test on filtrate, and carrying out mineral characterization on separated solids; a three-dimensional fluorescence spectrum is adopted to track composition conversion of the soluble organic matter in the reaction process; and analyzing the component change of the supernate before and after the reaction by adopting Fourier transform ion cyclotron resonance mass spectrometry. The influence mechanism of DOM on phosphorus and chromium fate in mineral / water interface molecular fractionation is disclosed from the molecular level, and a scientific basis is provided for collaborative migration risk assessment of phosphorus and heavy metal in acid mine wastewater irrigation area farmland.

The invention provides a method for detecting the grafting rate of anion exchange resin, which is characterized by comprising the following steps: tabletting treatment: applying first pressure to a resin sample containing anion exchange resin, the pressure value of the first pressure being 15-45MPa, and thus preparing a tabletting sample; and grafting rate detection: carrying out X-ray fluorescence spectrum test on the tabletting sample, determining the content of characteristic elements in the tabletting sample, and calculating the grafting rate of the anion exchange resin based on the content of the characteristic elements. The characteristic elements are selected from at least one of elements contained in the anion exchange resin and elements introduced into the anion exchange resin after the anion exchange resin is pretreated. According to the scheme, on the basis of XRF detection, a certain pressure is applied to the resin sample before detection, the resin sample is tableted, and the obtained tableted sample is used for XRF detection, so that the accuracy of anion exchange resin grafting rate detection is improved to a great extent.

The present application relates to a perovskite test device and a battery production system. The perovskite test device comprises a box body (100), an object placement platform (200), a first test mechanism (300) and a second test mechanism (400); the object placement platform (200) is arranged in the box body (100) and is used for placement of a sample; the first test mechanism (300) is used for emitting first test light, and acquiring the fluorescence spectrum of the first test light passing through the sample; the second test mechanism (400) is used for emitting second test light, and acquiring absorption and scattering spectra of the second test light passing through the sample. The battery production system comprises the perovskite test device. With regard to the perovskite test device and the battery production system, the test device meets different spectral test requirements, simplified design of the overall structure of the test device is facilitated, and the space utilization rate of the test device is optimized.

The application provides a method for detecting the content of each component in a mixture, which is mixed by various inorganic raw materials, and comprises the following steps: step 1, grinding, mixing and uniformly taking a certain amount of each of the to-be-detected substance and various raw materials thereof as samples; step 2, heating and calcining each sample to obtain the ignition loss value of each sample, and then performing a melting sheet treatment on each sample; step 3, using an X-ray fluorescence spectrometer to measure each sample after the melting sheet treatment, combining the corresponding ignition loss value, obtaining the oxide content in the to-be-detected substance and various raw materials thereof, and obtaining the oxide content corresponding to the to-be-detected substance and various raw materials thereof and the characteristic spectrum; and step 4, according to the oxide content and the characteristic spectrum of the to-be-detected substance and various raw materials thereof, analyzing the content of each raw material in the to-be-detected substance by spectrum fitting and least square method algorithm. The application can quickly and accurately detect the component content of mixtures such as cement and soil, and confirm whether the product is qualified.

The invention relates to an element content test method, which comprises: determining a final calibration curve, which is a curve for reflecting the relationship between the fluorescence intensity of a target metal element in a metal liquid sample to be tested and the content of a corresponding target metal element in a precursor prepared from the metal liquid sample to be tested; the method comprises the following steps: measuring a to-be-measured molten metal sample through X-ray fluorescence spectrometry to obtain the fluorescence intensity corresponding to each metal element, and obtaining the content of each metal element in a precursor obtained from the to-be-measured molten metal sample according to the fluorescence intensity. According to the method, whether the metal content in the product meets the process requirement or not can be judged by detecting the metal content in the precursor molten metal, the detection efficiency is improved, and the yield of the product is increased.

1. Name of the designed product: Scientific camera (GLORIA 4.2 Plus). 2. Use of the designed product: The designed product is used for microimaging, for capturing biophoton correlation fluorescence spectroscopy, for direct imaging in high-energy physics, for recording astronomical phenomena such as solar physics, orbit tracking, etc. in experiments in cell biology and electrophysiology. 3. Design points of the designed product: in shape. 4. Picture or photograph best indicating the design points: perspective view.

The invention provides a fluorescent anti-forgery ink luminescence effect characterization and quality control method, which comprises the following steps: adding a fluorescence correction agent into a solvent for constant volume, and preparing a standard solution; coating the printing ink on the surface of paper or dispersing the printing ink into a solvent to prepare a color developing sample or a solvent dispersing sample; respectively detecting and analyzing the ink sample and the fluorescence correction agent standard solution by adopting a fluorescence spectrophotometer, and correcting the fluorescence spectrum peak of the ink sample based on the response of the fluorescence correction agent to obtain a sample correction spectrogram; and constructing a quality control interval of the fluorescence response of the ink sample by taking the fluorescence response in the correction spectrogram of the series of ink samples as a data point, and evaluating the quality of a subsequent to-be-detected sample. The invention provides a sample preparation, correction and quality control method of a fluorescent anti-counterfeiting ink luminescence effect characterization system for the first time, provides a quantitative evaluation mode for fluorescent anti-counterfeiting, and solves the problems of poor visual observation accuracy and large subjective influence.

The invention relates to a spatial displacement laser spectrum detection method for wood identification. The method comprises four steps of instrument initialization, surface layer laser spectrum detection, base layer spatial displacement spectrum detection and comprehensive spectrum analysis of a detection target. The beneficial effects are that the same infrared laser is used as a laser pumping source of the infrared photonic crystal fiber and an infrared laser source for spatial displacement spectrum detection. The infrared absorption spectrum of the target surface layer and the infrared laser Raman and fluorescence spectrum of the base layer in the same wave number section can be detected at the same time, so that the material identification of the surface layer and the base layer is realized at the same time. Meanwhile, the wave number resolution of the infrared spectrum Fourier transform spectrum module is high, so that the high-resolution infrared laser Raman and fluorescence spectrum of the base layer can be obtained, and fine spectrum data is provided for base layer material identification. And the requirement for on-site rapid detection of wood products is met.

Aspects of the present disclosure include methods for spectrally parsing light of fluorophores having overlapping fluorescence spectra in a sample using adaptive measurement variances. A method according to certain embodiments includes detecting light from a sample particle comprising a plurality of fluorophores having an overlapping fluorescence spectrum with a light detection system, determining a measurement variance of the detection light for each particle, and spectrally resolving the light of each fluorophore in the sample by a weighted least squares algorithm using the measured variance determined for each particle. In some embodiments, a spectral unmixing matrix is calculated through a weighted least square algorithm using an adaptive measurement variance model. Systems and integrated circuit devices (e.g., field programmable gate arrays) for practicing the subject methods are also described. A non-transitory computer-readable storage medium is also provided.

The invention discloses a high-resolution cross-scale X-ray fluorescence spectrum high-flux characterization device and method. The device comprises a mu-XRF light source (an X-ray tube and a capillary X-ray lens), a plurality of SDD detectors, a sample box and a two-dimensional mobile platform which are sequentially arranged from top to bottom, x-rays emitted by the X-ray tube are restrained by the capillary X-ray lens into focuses with the diameter of 5 microns to vertically irradiate a sample, the whole mu-XRF light source adopts a fixed support structure capable of moving up and down, and cross-scale adjustment of beam spots in the range of 5 microns to 1 mm on the surface of the sample is realized; the plurality of SDD detectors are arranged at the periphery of the capillary X-ray lens in a surrounding manner at a set inclination angle, and synchronously collect spectral information of X-ray fluorescence; a sample box is placed on the two-dimensional moving platform, and the sample box can contain plane samples of different sizes. According to the invention, a high-throughput XRF device structure is independently developed, and rapid and accurate cross-scale X-ray fluorescence spectrum high-throughput quantitative characterization can be realized.

4-methyl-1, 2, 3-thiadiazole-5-formic acid (HT) is used as a ligand and reacts with lanthanum nitrate hexahydrate to synthesize the thiadiazole lanthanum complex [LaT3. (H2O) 2] n, the structure of the complex is characterized through single crystal-X-ray diffraction, infrared spectroscopy, elemental analysis, ultraviolet spectroscopy and thermogravimetric analysis, the fluorescence performance of the complex is measured, and the thiadiazole lanthanum complex is obtained. The interaction of the lanthanum complex with calf thymus DNA (CT-DNA) and human serum albumin (HSA) is researched through ultraviolet and fluorescence spectra. The coordination compound belongs to a triclinic crystal and a Pi space group. Research on the biological activity of the lanthanum complex shows that the lanthanum complex shows good biological activity, and can be beneficial to development of novel antibacterial drugs, help to promote research and development of anti-cancer drugs and enrich the content of medicinal chemistry and pharmacology. Different types of compounds are combined or have a synergistic effect, so that a novel medicine with unique performance and advantages is developed.

A laser-induced Raman and fluorescence spectroscopic test system includes a laser module, a harmonic beamsplitter, a frequency-doubling crystal, a first cavity mirror, a sample cell, a second cavity mirror, and a spectroscopic detection unit. A laser beam output by the laser module sequentially passes through the harmonic beamsplitter, the frequency-doubling crystal, and the first cavity mirror. Two sides of the harmonic beamsplitter are plated with a highly transmissive film and a highly reflective film, and the harmonic beamsplitter reflects a laser beam of a required wavelength to the sample cell. The second cavity mirror is configured for returning a laser beam from the sample cell. The harmonic beamsplitter, the first cavity mirror, the second focusing lens, and the second cavity mirror form a dual-beam waist laser resonator cavity. The first cavity mirror and the second cavity mirror are spherical mirrors and are plated with different highly reflective films.

The invention relates to an underground water nitrogen metabolism function prediction and regulation method based on a three-dimensional fluorescence spectrum and automatic machine learning. The method comprises the following steps: collecting underground water microbial gene sequencing serial numbers in literatures and fluorescence emission spectrum data of corresponding water samples; according to the obtained gene sequencing data serial number, downloading microbial gene sequencing data, and carrying out normalization processing on required emission spectrum data; selecting a functional gene reflecting underground water nitrogen metabolism capability and calculating relative abundance; and constructing a machine learning model of underground water nitrogen metabolism. The selected optimal model can accurately predict and understand underground water nitrogen metabolism, reveal the influence of DOM fluorescence properties on an underground water ecosystem, and can be used for predicting the underground water microorganism nitrogen metabolism function of an unknown area.

The present invention provides a high-precision, universal method for quantitatively analyzing the composition of multiple fluorescent substances. The method comprises: preprocessing raw spectral data of the multiple fluorescent substances to obtain spectral datasets; segmenting the spectral datasets; establishing a quantitative analysis model for crosstalk fluorescence spectroscopy based on the segmented spectral datasets, and performing quantitative analysis of the fluorescent substance components based on the quantitative analysis model. Compared with existing three-dimensional fluorescence spectral correction methods, the crosstalk fluorescence spectroscopy analysis method of the present invention is a more complete analysis method with higher quantitative analysis accuracy. Furthermore, the method development process does not rely on three-dimensional spectra, making it universal.

The present invention discloses a method for dual-ratio fluorescence detection of morphine in blood using nitrogen-doped carbon quantum dots; the present invention uses m-phenylenediamine and spermidine as carbon and nitrogen sources, and synthesizes nitrogen-doped fluorescent carbon quantum dots with high fluorescence quantum yield by microwave method; due to the fluorescence resonance energy transfer effect between morphine and carbon quantum dots, in the presence of morphine, the fluorescence of carbon quantum dots decreases at 350 nm, while increases sharply at 456 nm, and the ratio of the fluorescence intensity at 350 nm to that at 456 nm has a certain linear relationship with the morphine concentration, based on which a fluorescence spectrophotometry for detecting morphine in blood is established; the nitrogen-doped fluorescent carbon quantum dots prepared by the present invention have significant fluorescence sensitization and quenching effects on morphine, and have strong selectivity, and are used for the fluorescence determination of morphine in blood, with the characteristics of high sensitivity and specificity.