475 results about "Fluorescence spectra" patented technology

Measurements of fluorescence spectra of fluid samples recovered downhole are processed to give the fluid composition. The processing may include a principal component analysis followed by a clustering method or a neutral network. Alternatively the processing may include a partial least squares regression. The latter can give the analysis of a mixture of three or more fluids.

The invention provides a method used for simultaneous detection of three food-borne pathogenic bacteria based on multicolor upconversion fluorescence labeling. According to the method, three upconversion materials with differentiable fluorescence spectrums are used for forming multicolor upconversion fluorescent nanoprobes via respective connection with aptamers of staphylococcus aureus, vibrio parahaemolyticus, and salmonella, and complementary oligonucleotide single chains of the aptamers are connected with magnetic nanoparticles so as to form nano-composites. When bacteria to be tested are in a detection system, double chain unwinding is realized because of specific binding of the pathogenic bacteria with corresponding aptamers; it is possible to realize simultaneous quantitative determination of staphylococcus aureus, vibrio parahaemolyticus, and salmonella by monitoring upconversion fluorescence signal strength at 477nm, 550nm, and 660nm, detection linear range ranges from 50 to 1000000cfu/ml, and detection limits are 25cfu/ml, 10cfu/ml, and 15cfu/ml respectively. The method is used for detection of pathogenic bacteria, is high in sensitivity, is rapid and convenient, and can be used for detection of the three pathogenic bacteria in food such as milk and shrimp meat; and results are accurate and reliable.

The invention discloses an automatic detection system for the traditional-Chinese-medicine quality. Traditional-Chinese-medicine original images are collected, outlines of target areas are partitioned, the images are subjected to noise removing, a neural network PCNN corresponds to the images, central neuron corresponds to pixel points of the images, multi-wavelength LED lamps are illumed respectively, several LED lamps capable of motivating remarkable fluorescence signals are selected and alternately illumed, traditional-Chinese-medicine samples with fluorescence spectrums of 300 nm-1,100 nm are collected, the one-dimensional time-series signal characteristics of all two-dimensional images are extracted, characteristic information is stored, the airspace characteristics of traditional-Chinese-medicine microscopic images are extracted, and the traditional-Chinese-medicine quality is detected. According to the automatic detection system, the traditional-Chinese-medicine external parameters are synthetically evaluated with the electronic technology, the traditional-Chinese-medicine inherent quality is automatically detected by combing traditional-Chinese-medicine chemical-component content parameters, safety detection parameters and conventional detection parameters, the detection standard is objective and uniform, and accurate medicine making can be achieved.

The invention discloses a wide-view-field chromatography hyperspectral microscopic imaging method and device based on space-time focusing, and belongs to the technical field of microscopic spectral imaging and analytical chemistry. According to the method, ultra-short pulse lasers are generated through an ultra-short pulse laser source, focusing lines are generated in a sample through space-time focusing, excited fluorescence is collected, stray light is filtered out through con-focal optical slits, spectral information (x, lambda), of the sample is acquired through fluorescence spectral information collecting, and finally sample (x, lambda, y, z, t) five-dimensional information is acquired through three-dimensional space scanning and delayed scanning. The device comprises the ultra-shortpulse laser source, a light beam conversion system, a line scanning system based on space-time focusing, an optical microscopic system and a filtering and synchronous spectrum con-focal detection system. Acquisition of the spectral information in the filtering and synchronous spectrum con-focal detection system is synchronous with line scanning trigger signals in the line scanning system in combination with the space-time focusing technology. The method and device have the advantages of being wide in view field, high in space resolution, high in time resolution, high in spectral resolution andthe like.

The invention relates to a copper-doped all-inorganic halogen perovskite fluorescent material and a preparation method and application thereof. The material has structural formula CsPb1-xCuxBr3, wherein X is in the range of 0-1; the material is a light yellow or yellow powder, and in cubic phase, and has a space group as below. The method is as below: dissolving in an organic solvent at high temperature for further reaction, washing with a hexane or toluene solvent by multiple times, purifying to obtain the copper-doped all-inorganic halogen perovskite fluorescent material with size of 10-30nm. By measuring of the UV visible (wavelength range of 350-700nm) and fluorescence spectra (excitation wavelength is 360nm with), with the increase of doping amount of copper, the absorption wavelength and corresponding fluorescence emission wavelength show the red shift phenomenon, at the same time, the fluorescence quantum yield also changes. The preparation method of the invention is simple, green and environment-friendly, and has good application potential in the preparation of LED.

The invention discloses 2-micron luminous rare-earth ion-doped germanate laser glass and a preparation method thereof. The mol percentage composition of the glass is as follows: 60 to 65 percent of GeO2, 15 to 20 percent of BaF2, 2 to 13 percent of Ga2O3, and 2 to 13 percent of Re2O3ReF3; wherein, Re is the rare-earth elements of La, Yb, Tm and Ho. The rare-earth ion doping mode of the glass is: single doping of Tm, double doping of Yb and Tm, double doping of Yb and Ho, double doping of Tm and Ho, or three doping of Yb, Tm and Ho. Rare-earth ions are introduced in the form of rare earth oxides or rare earth fluorides and can all obtain the glass with stability and excellent luminous performance. Test result shows that the germanate glass in the invention has higher transmission rate and wider transmission range. A fluorescence spectrum test shows that the germanate laser glass of the invention can obtain excellent fluorescence emitting approaching to 2-micron. The laser glass of the invention is also suitable for preparing 2-micron optical fiber perform cores.

The invention discloses a rhodamine derivative and a preparation method and application thereof. The rhodamine derivative is prepared by reacting rhodamine hydrazide and 4-chloro-7-nitro-2,1,3-benzoxaoxadiazole in the presence of an acid binding agent. The Cu<2+> and Fe<3+> can be respectively detected at high selectivity and high sensitivity. The designed and synthesized structure is short in synthetic route and mild in reaction conditions, the obtained derivative can be used for an aqueous phase system, and the ultraviolet-visible absorption spectrum and fluorescence spectrum are insensitive to the acid-base property of the system.

The invention relates to a method for comprehensively testing the stability of a deep ultraviolet optical element. The method comprises the following steps of: measuring the absorption loss absolute value of the deep ultraviolet optical element by adopting a laser calorimetry technology and calibrating a photo-thermal signal amplitude; monitoring real-time change of the absorption loss of the deep ultraviolet optical element in the deep ultraviolet laser irradiation process by adopting a photo-thermal technology; measuring a fluorescence spectrum of the deep ultraviolet optical element and real-time change of the fluorescence spectrum by adopting a laser induction fluorescent technology; and monitoring the performance stability of the deep ultraviolet optical element by measuring the absorption loss of the deep ultraviolet optical element and the real-time change of the fluorescence spectrum.

The invention discloses a multichannel fluorescence spectra biological aerosol particle detecting apparatus. The apparatus comprises the following components: an aerosol air-flow generation unit for generating aerosol particle gas; a laser detection unit, which is arranged corresponding to the aerosol air-flow generation unit, in order to carry out laser irradiation and detection of partial aerosol particle gas outputted from the aerosol air-flow generation unit, and to obtain diffusion light signals and intrinsic fluorescence signals of the aerosol particles; a total flow controlling and exhausting unit, which is arranged corresponding to the aerosol air-flow generation unit, in order to carry out filtering and discharge of aerosol particles which are outputted from the aerosol air-flow generation unit and do not pass through the laser detection unit and aerosol particles which pass through the laser detection unit; an analyzing unit, which is used for accurately determining classes of the aerosol particles according to the diffusion light signals and the intrinsic fluorescence signals of the aerosol particles.

The present disclosure describes a method of detecting a drug marker in urine a urine sample using a toilet. The drug markers are fluorophores each of which emits a unique fluorescence spectra. Accordingly, the method does not detect the drug but rather, the drug marker. A user who has consumed the drug with its unique drug marker then urinates into the toilet and a urine sample is captured. The toilet includes a mechanism for fluid handling which diverts urine into a fluorescence spectrometer. The fluorescence spectrometer screens the urine for drug markers based on their unique fluorescent spectra. The toilet may include a controller which quantifies the drug marker. The fluorescent spectrometer may detect multiple drug markers in a single urine sample. This method may be used to confirm drug compliance, test for illicit drugs, identify amounts of drugs consumed, and other uses described herein.

The invention discloses an iron oxide/bismuth tungstate composite photocatalyst, a preparation method of the iron oxide/bismuth tungstate composite photocatalyst and the application of the iron oxide/bismuth tungstate composite photocatalyst. The iron oxide/bismuth tungstate composite photocatalyst has a Fe2O3/Bi2WO6 XRD (X-ray diffraction) diffraction pattern as shown in Figure 1 of the specification and a composite morphology as shown in Figure 2 of the specification. 10-30nm of Fe2O3 nano-particles are precipitated on the surface of Bi2WO6 by a soaking-low temperature roasting technology. The invention represents the change of the structure, the morphology, the ultraviolet-visible absorption spectrum and the fluorescence spectrum of the material before and after being modified in details, and researches the catalytic degradation of the visible light of the iron oxide/bismuth tungstate composite photocatalyst to the activity of the dyestuff rhodamine B (RhB). The result shows that Fe2O3 particles with the mean grain sizes of 20nm are dispersed on the surface of a nanosheet unit of a Bi2WO6 superstructure, the visible light response range of the Fe2O3/Bi2WO6 composite photocatalyst is obvious in bathochromic shift, and the composition probability of photon-generated carriers can be effectively restrained as well. When the toasting temperature is low temperature of 200DGE C, and the Fe element content is 0.1% (wt%), the photocatalytic activity is optimal, and the efficiency of the visible-light catalytic degradation RhB can be improved by 20% compared with that of the un-composited visible-light catalytic degradation RhB.

The invention relates to a carbon quantum dot-copper ion fluorescent probe and a preparation method and application thereof. The method includes that carbon quantum dots with strong fluorescence are synthesized by the aid of a microwave hydrothermal method, fluorescence strength of the carbon quantum dots are greatly reduced by the aid of copper ions, the copper ions are composited on surfaces ofthe carbon quantum dots, surface energy is transferred, CQDs/Cu<2+> with weak fluorescence is formed, a glucose solution is added, pH value is adjusted to 7, heating is performed at the temperature of80DEG C, glucose and the copper ions undergo 'copper mirror reaction' to be oxidized to gluconic acid, and the copper ions are reduced to be precipitated to be Cu2O2. The fluorescence spectrum test shows that after the glucose solution is added, glucose is catalyzed and oxidized through the copper ions on the carbon quantum dots CQDs for reaction and is removed from surfaces of the CQDs, and thestrong fluorescence on the CQDs is restored. The carbon quantum dot-copper ion fluorescent probe based CQDs/Cu<2+> is applicable to effective detection of the glucose under non-enzymatic environment.

The invention discloses a citrus vein phloem degeneration detection and classification method based on the D-S theory through multi-source data fusion. The method includes utilizing a hyperspectral image collecting platform, a visible spectrum image collecting platform and a fluorescence spectra image collecting platform to collect image information of citrus leaf samples, performing classification of the symptoms of the citrus vein phloem degeneration on the various spectrum collected image information, and acquiring the identification rate of each classification of the symptoms of three varieties of spectrum; allowing the identification rates of three varieties of spectrum to serve as evidence sources, allocating PBA values to each proposition of an evidence identifying frame, and establishing credibility vectors of the evidence sources; allowing the credibility to serve as a discount factor to adjust the BPA values to each proposition of the evidence identifying frame; fusing the adjusted BPA values according to a Dempster combination rule, acquiring a comprehensive identification rate of the symptoms of the citrus vein phloem degeneration, and implementing correct diagnosis of the symptoms of the citrus vein phloem degeneration. According to the method, the identification rates of the hyperspectrum, visible spectrum and fluorescence spectra are fused, the comprehensive identification rate of the symptoms of the citrus vein phloem degeneration is acquired, and the correct diagnosis of the symptoms of the citrus vein phloem degeneration is implemented.

The invention provides a fluorescent probe compound used for detection of acetate, and a preparation method and applications thereof, and belongs to the field of fluorescent probe compounds and preparation of fluorescent probe compounds. The fluorescent probe compound N, N'-2-[3-hydroxy-4-(2-benzoxazole)phenyl]carbamide can be used as a ratiometric fluorescent identification probe for concentration detection of acetate, and is used for detecting fluorescence peak intensity at 470nm and fluorescence intensity at 380nm on a fluorescence spectra. Sensitivity, and selectivity of the fluorescent probe compound on acetate detection are relatively high, and reproducibility is excellent. The fluorescent probe compound can be used for acetate detection in the fields of biochemistry, environmental chemistry, and the like.

The object of the present invention is to provide a substance, which is easy to handle and enables the measurement of ATP with a high sensitivity regardless of the concentration of protein, and further a measuring method of ATP using the substance. Such object is solved with a fluorescence labelled fusion protein obtained by attaching two types of fluorescent substances of potential donor and acceptor for fluorescence resonance energy transfer (FRET) respectively to a protein which can cause structural changes depending on ATP binding, namely ε protein, which is the subunit of ATP synthetase, and further solved by contacting the fluorescence labelled fusion protein with a subject substance and then measuring the fluorescence spectra.

The invention discloses a tea/cosmetics quality detecting method based on two-dimensional correlation spectra. The method comprises the following steps: spectra acquisition comprising the steps of illuminating samples through LED, motivating visible near-infrared reflective spectra or fluorescence spectra of the samples and acquiring; spectrum preprocessing comprising the steps of preprocessing the acquired fluorescence spectra or reflective spectra; two-dimensional correlation spectrum obtaining comprising the steps of selecting feature regions from multiple different sample spectra, and carrying out synchronous correlation or asynchronous correlation calculation, to obtain synchronous spectra or asynchronous spectra; detection model establishment comprising the steps of establishing a sample two-dimensional correlation spectrum and sample level detection evaluation model based on a stoichiometry method; and sample quality detection comprising the steps of acquiring a dynamic spectrum of a new to-be-detected sample, calculating a two-dimensional correlation spectrum, bringing into the detection model, and analyzing to obtain a sample quality detection result. Based on the LED, the improvement on a quality detection system is relatively small, the cost is low, besides, rapid and effective high-precision detection can be satisfied, and the practicability is relatively high.