537 results about "Red fluorescence" patented technology

The invention provides a ratio type molecular imprinting fluorescence sensing detection method based on a metal organic framework and nitrogen-doped carbon dots, the advantages of N-CDs, Eu-MOF and a molecular imprinting layer are fused, in the presence of target molecules, the blue fluorescence (430nm) of the N-CDs is effectively enhanced due to non-radiative recombination caused by the surface defect state of the CDs, and the red fluorescence (660nm) of the Eu-MOF remains unchanged. According to the ratio type molecularly imprinted fluorescent sensing detection method, while a fluorescent response signal is displayed, the color of the imprinted polymer changes along with different concentrations of the target molecules, and sensitive visual detection of the target molecules can be realized, so that specific sensitive detection of the target molecules in a complex sample is realized; the method has the advantages of high sensitivity, simplicity and convenience in operation, good reproducibility, strong anti-interference performance and the like. According to the method, rapid and sensitive detection of organophosphorus pesticides, toxic agents and other imprinted molecules can be realized by preparing imprinted polymers of different target molecules without fluorescence interference, and the method has a wide application prospect.

The invention discloses a cable electric leakage detection device and detection method, and belongs to the field of cable electric leakage detection. A cable electric leakage detection device comprises a base. A detection rod; and a cleaning brush. Air is blown out through the cleaning brush, and the cleaning brush is matched to brush the outer surface of the cable, so that dust and other impurities at the damaged and crack positions of the outer surface of the cable are cleaned out, the cleanliness of the cable is ensured, and red fluorescence labeling liquid is released at the damaged and crack positions of the outer surface of the cable; the cable damage and crack detection device can mark all damage and cracks of a cable, observation of subsequent personnel is facilitated, the detection efficiency and quality of the damage and cracks of the cable are improved, eye fatigue of detection personnel is reduced at the same time, red fluorescent marking liquid can be turned into green under irradiation of an ultraviolet lamp, and the detection efficiency is improved. Therefore, the personnel can visually judge the electric leakage part of the cable according to the color, the detection accuracy of the electric leakage part of the cable is improved, and the burden of the personnel is reduced.

The invention belongs to the technical field of biology, and discloses a stable protective agent, a cell antigen dry sheet and a preparation method and application of the dry sheet, the stable protective agent comprises glycerin with the volume fraction being 0.4%, gelatin with the mass volume fraction being 0.1%, EDTA with the mass volume fraction being 0.1 mM, trehalose with the mass volume fraction being 0.03% and resveratrol with the mass volume fraction being 100 [mu] M. The stable protective agent is adopted for preparing the cell antigen dry sheet, and the cell antigen dry sheet is applied to CBA detection. The stable protective agent has good permeability, can penetrate through cell membranes to enter cells, provides a protection effect inside and outside the cells, has moisture retention and oxidation resistance, can prevent cell deformation and cell fixing layer shedding, and can well maintain the stability and reliability of antigen proteins, and the prepared cell antigen dry sheet can be stored for a long time, and has a good application prospect. The antigenicity of a membrane signal index is not damaged. When a positive sample is detected, obvious green fluorescence cells can be seen, red fluorescence quenching is avoided, and co-localization of red fluorescence and green fluorescence can be observed conveniently.

The invention discloses an MOF-CQD enzyme-sensitive FRET hydrogel diagnosis and treatment probe as well as a preparation method and application thereof, and belongs to the technical field of biomedical detection and treatment. The probe takes a carboxyl carbon quantum dot (CQD) as a donor and a metal organic framework (MOF) as an acceptor, and the donor and the acceptor are connected through a replaceable enzyme response polypeptide bridge; when the fluorescence is complete, FRET is generated to quench the CQD fluorescence, the FRET is interrupted after the target enzyme cuts off the peptide bridge, and the blue / red fluorescence ratio is changed to realize nanomole-level quantitative detection and has self-correction capability. The probe is packaged in a four-arm PEG transparent hydrogel which does not need a photoinitiator and can be quickly self-crosslinked, and can be prepared into a film, a tooth socket and the like for POCT (point-of-care testing) of parts such as an oral cavity / skin and the like. After detection, the MOF is activated by illumination of 630-660 nm to generate active singlet oxygen, so that local antibacterial or anti-tumor treatment is realized, and a diagnosis and treatment integrated scheme is constructed.

The invention is about a method of marking ink which is only used to defend fake. The composition of it is: lipidol or lipid, surface active agent, integration agent, water, buffering agent. Their mass percents are: 1,2-hexylene glycol: 5%-15%, butanol: 1-5%, DH-1: 5-10%, EDTA: 0.1-0.5%, MS-1: 0.1-1%, water: the rest. The process is: a. dissolving the colorant in water, b. put the correct percent of 1,2-hexylene glycol and butanol into the solvent, then dropping the MS-1 and EDTA solution when mixing the solvent for 30-50 min, c. put the rest precent of water into the printing ink box. The picture and word would be shown red fluorescence in the UV but blank in the usual light.

A phosphor composition includes a red phosphor material having a red decay rate and a green phosphor material having a green decay rate. The red phosphor material includes a Mn4+ doped phosphor of Formula I and a Eu3+ doped uranium phosphor, and a difference between the red decay rate and the green decay rate is no more than 7 ms, AxMFy:Mn4+ (I), wherein A is Li, Na, K, Rb, Cs, or a combination thereof; M is Si, Ge, Sn, Ti, Zr, Al, Ga, In, Sc, Hf, Y, La, Nb, Ta, Bi, Gd, or a combination thereof; x is an absolute value of a charge of the MFy ion; and y is 5, 6 or 7. A device is also provided.

The invention is suitable for the technical field of inorganic luminescent materials, and provides a fluorescent powder material based on a double-perovskite structure and a preparation method and application thereof. The general chemical formula of the fluorescent powder is Ca2AlNbO6: xEu < 3 + >, wherein x is a molar fraction of 0.06 to 0.30; the excitation spectrum coverage range of the fluorescent powder under the condition of monitoring the emission wavelength of 615 nm is 260-500 nm, and the emission main peak is located at 615 nm; when x is equal to 0.18, the quantum efficiency under the excitation of 396nm ultraviolet light is greater than or equal to 91%, and the red light emission ratio is greater than or equal to 85%. According to the invention, Ca2AlNbO6 double perovskite is taken as a substrate, and a red fluorescent powder material with wide-spectrum excitation and high quantum efficiency is designed through Eu < 3 + > high-concentration doping and local symmetry regulation and control design engineering, so that the characteristics of high quantum efficiency, efficient red light emission, wide-spectrum excitation and excellent concentration quenching resistance are realized.

The invention relates to a double-probe detection reagent for detecting salmonella typhimurium and a preparation method of the double-probe detection reagent, and belongs to the technical field of food safety. The double-probe detection reagent is formed by respectively packaging a magnetic separation probe reagent solution and a fluorescent nano-enzyme probe reagent solution; the magnetic separation probe reagent liquid is used for specifically binding salmonella typhimurium and carrying out separation and enrichment treatment on a detection sample; the red fluorescent nano-enzyme probe reagent solution is used for specifically combining the salmonella typhimurium subjected to separation and enrichment treatment and generating a salmonella typhimurium concentration dependent colorimetric signal and a fluorescent signal. The double-probe detection reagent disclosed by the invention is short in detection time and high in detection sensitivity when being used for detecting salmonella typhimurium, and has relatively good specificity on common type strains. According to the invention, the specific surface area is high, the peroxidase-like activity is excellent, and the high-sensitivity capture efficiency is enhanced; according to the invention, mutual verification is carried out between the dual-mode signals, an internal proofreading effect is achieved, and the detection result is accurate.

The invention relates to the technical field of organic supramolecular chemical materials, in particular to an octyloxy-modified imine gelator, bi-component gel of the octyloxy-modified imine gelator and a preparation method and application of the octyloxy-modified imine gelator. The gelator is a symmetric o-octyloxy modified p-phenylenedialdehyde-maleonitrile imine gelator, and has an obvious aggregation-induced emission property; the gelator and the cholesteryl half-ester gel can form double-component organic gel without fluorescence emission in an organic solvent; the fluorescence-emission-free double-component gel formed in tert-butyl alcohol is red fluorescence-emission gel when meeting water, and is converted into blue fluorescence-emission gel when meeting NaClO, so that water and NaClO can be rapidly and intuitively detected; the gelator has fluorescence enhancement and blue shift after encountering NaClO in a solution state, has fluorescence'off-on 'detection on NaClO, has fluorescence emission intensity reduced after Hg < 2 + > is added in the solution state, and has fluorescence'on-off' detection performance on Hg < 2 + >.

The invention relates to the technical field of organic material detection, in particular to an imine molecular sensor with a five-detection function, two-component gel as well as a preparation method and application of the imine molecular sensor. The imine molecular sensor has three signal responses of fluorescence on-off, ultraviolet absorption and color change to Fe < 3 + >, Co < 2 + > and Ni < 2 + > in a solution state, and has ultraviolet absorption and fluorescence on-off dual-detection performance to acid and alkali changes; the imine molecular sensor and cholesteryl half ester can form two-component gel through a heating-low-temperature ultrasonic cooling method; after Fe < 3 + >, Co < 2 + >, Ni < 2 + >, NaOH and HCl are respectively added, the orange of the gel becomes milky white, reddish brown, transparent red, milky white and milky white under sunlight, and the fluorescence of the orange of the gel disappears under an ultraviolet lamp, so that the rapid and sensitive detection of Fe < 3 + >, Co < 2 + >, Ni < 2 + >, acid and alkali under two states of the imine molecular solution and the gel is realized. The imine molecular sensor provided by the invention has the advantages of mild synthesis conditions, simple preparation and the like, and creates favorable conditions for popularization and application of the imine molecular sensor.

The invention discloses a near-infrared fluorescent probe for detecting ONOO <-> as well as a preparation method and application of the near-infrared fluorescent probe, and belongs to the technical field of peroxynitroso ion detection. The near-infrared fluorescent probe for detecting ONOO <-> provided by the invention is high in detection speed, and the highest fluorescence intensity can be reached within 60 seconds; the reaction is obvious and easy to observe, when the compound reacts with ONOO <->, strong red fluorescence can be generated, and the change of the color of the solution can be observed by naked eyes; the selectivity is strong, the sensitivity is high, the interference of other biological molecules and active substances can be effectively avoided, the accuracy and the reliability of a detection result are ensured, and the lowest detection limit can reach 107nM; the hydrogel has good biocompatibility, is low in toxicity in a living body, and does not generate adverse effects on normal physiological functions of a biological sample; the provided preparation method is simple and easy to operate, the raw materials are low in cost and easy to obtain, the synthesis efficiency is high, and the preparation method can be used for large-scale industrial production and has wide application prospects.

The invention discloses a watermelon transgenic screening expression cassette and application thereof, and belongs to the technical field of biology. According to the invention, an expression cassette of a TagRFP gene driven by a d35s promoter is constructed on a pCambia1300 vector, and a recombinant vector is obtained. A recombinant vector is introduced into watermelon cells by utilizing an agrobacterium-mediated genetic transformation technology, and a red fluorescent protein TagRFP gene is integrated into a watermelon genome, so that transgenic watermelons can be screened and identified by taking red fluorescence as an identifier in the whole growth period of watermelon genetic transformation. Compared with a traditional screening method, the screening method has the advantages that the screening process is greatly simplified, and the transgenic watermelon and the non-transgenic watermelon are clearly distinguished, so that the genetic transformation efficiency of the watermelon is remarkably improved.

The invention relates to Eu (II) doped double perovskite red fluorescent powder as well as a preparation method and application thereof, and belongs to the technical field of inorganic luminescent materials. According to the red fluorescent powder capable of being excited by the blue light, disclosed by the invention, high-performance red light emission is realized by doping Eu < 2 + > with an oxide Sr2B1-xB 'O6 (wherein B is lutetium (Lu), B' is tantalum (Ta) or niobium (Nb), and x is greater than or equal to 0.01 and less than or equal to 0.10 as a matrix). The novel red fluorescent powder can be applied to white light LED illumination. When the fluorescent powder is used in combination with green light or yellow light fluorescent powder in the prior art, efficient white light is expected to be realized under the excitation of blue light, so that the color rendering performance of a white light LED is absolutely improved.

The invention discloses a double-fluorescence-labeled engineering bacterium for in-situ tracing of horizontal transfer of plasmids in pseudomonas among bacteria as well as a construction method and application of the double-fluorescence-labeled engineering bacterium, pseudomonas is taken as an original strain, a green fluorescence strong expression component is integrated into a pseudomonas chromosome genome, and green fluorescence-labeled pseudomonas is obtained; a red fluorescence strong expression element is inserted into a multiple cloning site of a broad-host zygote, and is converted into the green fluorescence labeled pseudomonas to form a double-fluorescence labeled engineering bacterium. The double-fluorescence-labeled strain disclosed by the invention can generate corresponding green fluorescence or red fluorescence after being excited by a green or red fluorescence excitation wavelength; when the plasmids enter other bacteria under the action of conjugation or transformation, the recipient bacteria can only present red fluorescence under the excitation of the red fluorescence excitation wavelength, and the horizontal transfer condition of the plasmids in the pseudomonas bacteria among the bacteria under the in-situ condition can be accurately tracked through the intuitive method.

The invention provides fluorescent conversion type red fluorescent powder for display as well as a preparation method and application thereof, and belongs to the technical field of light-emitting display materials. Metal Sr, metal Al and metal Eu are mixed and smelted according to the stoichiometric ratio and then ground to prepare alloy powder, lithium aluminum hydride powder and the alloy powder are ground, mixed, calcined and ground again, and the red fluorescent powder for laser display with high brightness under blue light excitation is prepared. According to the invention, an alloying method is combined with a nitriding method, and the molar ratio (greater than 70%) of Eu < 2 + > (radiative transition) in all Eu elements in the prepared fluorescent powder product is greatly increased, so that the prepared red fluorescent powder has high color purity, high luminous efficiency and thermal stability, and meanwhile, a sample has an ultrahigh saturation threshold value under the excitation of blue laser; the material can be applied to a fluorescence conversion type laser display technology, and has huge potential for laser display devices.

The embodiment of the invention provides a low-blue-light LED light source, a preparation method thereof and a lighting device, the light source comprises a support, an LED chip arranged in the support and electrically connected with the support and a fluorescent layer packaging the chip, the fluorescent layer comprises a fluorescent powder composition, and the fluorescent powder composition comprises blue-green fluorescent powder, green fluorescent powder and red fluorescent powder; the LED chip is a purple light chip; the general chemical formula of the blue-green fluorescent powder is (Ba, Sr, Ca) < 1-x > Si2O2N2: xEu < 2 + >, the general chemical formula of the green fluorescent powder is (Lu, Ga) 3-yAl5O12: yCe < 3 + >, the chemical general formula of the red fluorescent powder is (Sr, Ca) (1-z) AlSiN3: zEu < 2 + > or (Sr, Ca) (2-z) Al2Si2N6: zEu < 2 + >. The light source can meet the requirement that the absolute spectral intensity of blue light in the range of 430-460 nm of the blue light band is lower than 0.1, and the requirement for healthy illumination is met.

The invention relates to a red fluorescent material excited by blue light, an LED device and fluorescent ceramic. The chemical formula of the red fluorescent material is La (2-x) MgNbO6.5: xEu < 3 + >, wherein x is more than or equal to 0.01 and less than or equal to 0.1. The preparation method comprises the following steps: weighing lanthanum oxide, magnesium oxide, niobium oxide and europium oxide raw materials according to a stoichiometric ratio, grinding and uniformly mixing; sintering the uniformly mixed powder in a muffle furnace at high temperature, and cooling to room temperature to obtain the red fluorescent material. Compared with the prior art, the novel oxide-based red fluorescent powder prepared by the invention can emit positive red light of which the central wavelength is 616nm under the excitation of 465nm blue light, and can be used for white light LED (Light Emitting Diode) luminescent devices and fluorescent ceramics.

The invention discloses a diamond low-frequency current measurement method with nonlinear response to magnetic field intensity, which is characterized in that two coils are wound on a magnetic flux collector with a communicated structure, a high-frequency (800Hz) high-voltage (7V) driving current is injected into one of the coils, a magnetic field generated by the coil is amplified through the magnetic flux collector and guided to an area where an NV color center magnetometer is located, and the NV color center magnetometer is located; and the signal is driven to enter a nonlinear response interval in the demodulated ODMR spectrum. A weak (1-50mV) to-be-measured low-frequency (0.1-10Hz) current signal is injected into the other coil, amplitude modulation is performed on the weak (1-50mV) to-be-measured low-frequency (0.1-10Hz) current signal by using the same frequency as the driving current, and the weak (1-50mV) to-be-measured low-frequency (0.1-10Hz) current signal is amplified by the magnetic flux collector and guided to the NV The microwave frequency is locked at the maximum slope point of the ODMR frequency spectrum through CW-ODMR phase-locked amplification, so that the relationship between the change of the red fluorescence signal intensity and the size of the external magnetic field is obtained, and the signal intensity of the low-frequency current magnetic field to be measured is measured according to the relationship.

The invention discloses a fixing reagent and method for double-color fluorescence detection of an anti-NMDAR antibody and application, the fixing reagent comprises paraformaldehyde and a mixture of methanol and acetone, and the mixture comprises 10-25% by volume of methanol, 75-90% by volume of acetone, 10-25% by volume of paraformaldehyde, 10-25% by volume of paraformaldehyde and 10-25% by volume of paraformaldehyde. The fixing effect is better by adopting paraformaldehyde with the mass-volume ratio concentration of 4% and a mixture of methanol with the volume fraction of 15% and acetone with the volume fraction of 85% in two steps. By adopting the fixing liquid and the fixing method, the antigenicity of NMDAR cannot be damaged, obvious green fluorescence cells can be seen in a positive sample, red fluorescence quenching is avoided, and co-localization of red fluorescence and green fluorescence can be observed by using a fluorescence microscope.

The invention relates to a fluorescence in-situ hybridization image result analysis method and system based on deep learning, and a medium. The method comprises the following steps: constructing an SEAM-Unet + + image segmentation model; a YOLO-SEM small target detection algorithm model is constructed; obtaining a cell precise segmentation map of a channel B; obtaining a red fluorescence probe distribution map; obtaining a green fluorescent probe distribution map; and combining the obtained accurate cell segmentation map, the red fluorescence distribution map and the green fluorescence distribution map into one map to obtain a relational graph of cell and probe distribution. According to the method, complex image scenes can be effectively processed, the analysis of various medical images is supported, the medical diagnosis efficiency is improved, personal errors are reduced, and the cell analysis and pathological detection capabilities in scientific research and clinical application are enhanced.

The invention discloses a red fluorescent silicon nanodot as well as a preparation method and application thereof. The method comprises the following steps: S1, weighing sulforhodamine 101, adding ultrapure water for dissolving, then adding N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, uniformly stirring, transferring the obtained mixture into a reaction kettle, and heating for reaction; and S2, after the reaction is finished, cooling to room temperature, purifying the obtained product by using a silica gel chromatographic column, eluting by using an eluent, collecting the eluent, and finally, freeze-drying to obtain the red fluorescent silicon nanodots. Compared with common blue-green fluorescence, red fluorescence emission has deeper tissue penetrability and background fluorescence interference resistance; the silicon nanodot provided by the invention not only has excellent light stability and high quantum yield, but also has characteristics similar to lipophilic cations, and can specifically target mitochondria in living cells; in addition, the silicon nanodots also show excellent imaging ability in zebrafish embryos and juvenile fish bodies.

The invention discloses a preparation method of Eu < 3 + >-doped black talc-based high-performance luminescent glass, and the prepared luminescent glass is a novel photoluminescent material matrix and can provide a new expansion space for a rare earth photoluminescent material. The luminescent glass is characterized by comprising the following chemical components in percentage by weight: 90wt% of black talc, 10wt% of CaO and 1-13wt% of Eu2O3. The preparation method comprises the following steps: weighing the three raw materials according to the mass ratio, uniformly mixing in a ceramic mortar, putting into an Al2O3 crucible, putting into a high-temperature muffle furnace, carrying out high-temperature melting at the melting temperature of 1600 DEG C, and keeping the temperature for 2 hours. Pouring the glass melt on a preheated stainless steel mold, placing the mold in a low-temperature muffle furnace for annealing treatment at the annealing temperature of 680 DEG C, and keeping the temperature for 10 hours; and cooling the annealing furnace to room temperature to obtain the black talc-based luminescent glass. According to the invention, a black talc high-value utilization technology is successfully developed, and the prepared luminescent glass can be excited by a 394 nm light source to emit red fluorescence with a fluorescence range of 520-750 nm and a main emission peak of 615 nm, and can be used as a red fluorescent material of a warm white light LED.

The invention relates to the technical field of backlight modules, and discloses a backlight module and a display device. A certain proportion of red dye is arranged in the optical component of the backlight module, the red light proportion in the backlight module is increased, and the red shift phenomenon of color points of the backlight module is actively caused; meanwhile, the proportion of red fluorescent powder and green fluorescent powder in the high-color-gamut LED is adjusted, the proportion of green light is properly increased, and visual effect screen body color point correction is achieved; the proportion of green fluorescent powder in the high-color-gamut LED is increased, so that the luminous efficiency of the LED can be improved, the thermal reliability can be improved, the upper limit value of driving forward current can be increased, and the high-color-gamut LED has advancement compared with a traditional white-light high-color-gamut LED; by means of the principle, scheme matching can be carried out according to requirements, the effect of improving the brightness of the backlight module is achieved, and an extreme cost design scheme is achieved.

The invention relates to the technical field of backlight modules, and discloses a backlight module and a display device. The optical component containing the red fluorescent powder is arranged in the light emitting direction of the blue light wafer of the backlight module, and the red shift phenomenon of color points of the backlight module is actively caused; meanwhile, quantum dots of a red light excitation wave band are greatly reduced or completely canceled in the quantum film in the light emitting direction of the optical component, and the quantum dot proportion of a green light excitation wave band is increased, so that the color dots are corrected, and the red shift is counteracted; meanwhile, due to the fact that quantum dots of the red light excitation wave band in the quantum film are greatly reduced, the stability of the quantum film is improved, the LED lamp panel can be driven to higher current, the LED light-emitting efficiency is improved, and the overall brightness of the backlight module is improved; and moreover, the color points can be adjusted by adjusting the proportion of the red wave band fluorescent powder, so that different liquid crystal panels can be matched, the composition of the quantum film can be kept unchanged, and the backlight module is more flexible and universal in actual production.

The present invention discloses a ratiometric fluorescent smart label for visually detecting the freshness of meat, and its preparation method and application. The smart label preparation method is specifically as follows: first, a ratiometric fluorescent indicator of gold-copper bimetallic nanoclusters (indicator) with red fluorescence and dual-ligand gold nanoclusters (internal standard) with green fluorescence is prepared; then, by a solution doping method, the ratiometric fluorescent indicator is added to a polyvinyl alcohol / polyethylene glycol solution to prepare a ratiometric fluorescent smart label; finally, a fluorescent colorimetric card is made based on the ratiometric fluorescent smart label, and the smart label is applied to the prediction of meat freshness grade and total volatile basic nitrogen content in combination with a smart phone. The ratiometric fluorescent smart label prepared by the present invention has higher accuracy and sensitivity than a colorimetric sensing indicator film; and the smart label is safe, biocompatible, biodegradable, and has strong mechanical properties, and has the function of real-time monitoring of the freshness of fresh meat and aquatic products.

The invention discloses a recombinant rabies virus genome plasmid for high-sensitivity expression of red fluorescent protein, a recombinant rabies virus as well as a preparation method and application of the recombinant rabies virus. The preparation method specifically comprises the following steps: (1) constructing the recombinant rabies virus genome plasmid for high-sensitivity expression of red fluorescent protein as shown in SEQ ID NO.2; (2) preparing a recombinant rabies virus for expressing the red fluorescent protein with high sensitivity; and (3) application of the recombinant rabies virus for high-sensitivity expression of the red fluorescent protein in neural circuit tracing. The recombinant rabies virus capable of highly sensitively expressing the red fluorescent protein can efficiently mark an upstream neural network in a retrograde manner, so that the problem of low efficiency of expressing red fluorescence in the existing method is solved; the method has wide application value and market prospect in the aspects of neural circuit structure and function analysis, neuron sparse marking, vaccine and drug research and development, disease model establishment, neural network loss and reconstruction detection, virus replication or pathogenic mechanism research and the like.

The invention belongs to the technical field of laser diode illumination and display, and particularly relates to a laser white light device for laser display and illumination and a preparation method thereof. Comprising a laser emission module and a fluorescence conversion module. The fluorescence conversion module comprises a pixelated transparent substrate, a green fluorescent powder unit and a red fluorescent powder unit; groove array structures which are arranged in a staggered mode are distributed on the upper side and the lower side of the pixelated transparent substrate respectively. The green fluorescent powder unit is arranged in the lower side groove array structure, and the red fluorescent powder unit is arranged in the upper side groove array structure; the laser emitting module emits laser from the lower portion of the pixelated transparent substrate to the upper portion, and the green fluorescent powder unit and the red fluorescent powder unit are excited to emit green light and red light respectively and then are fused to form white light. According to the invention, the heat dissipation performance of the fluorescence conversion module is improved, the reabsorption between red and green fluorescent powder is weakened, the luminous efficiency is improved, and a white light LD device with high brightness and high color rendering can be realized.

The invention relates to a dental plaque detection method and system based on ultraviolet image analysis. The method comprises the following steps: acquiring an RGB image of dental plaque; converting the RGB image into an HSV image; performing tooth region identification, single tooth segmentation and single tooth contour cutting on the HSV image in sequence to obtain each single tooth ROI pixel and a total tooth ROI pixel; extracting a red fluorescence characteristic region from the HSV image, and calculating to obtain a red fluorescence region pixel and a red fluorescence average brightness value; the dental plaque severity score is calculated according to the total tooth ROI pixel, the red fluorescence region pixel and the red fluorescence average brightness value, the severity of the dental plaque is quantified, a user can know the tooth health state more clearly, and then oral health is maintained. The change of the score value is beneficial to motivating the user to continuously monitor the dental plaque condition, so that the user can conveniently manage oral hygiene and health more finely, and the user experience is improved.

The present invention relates to a dual-probe detection reagent and a preparation method for detecting Salmonella typhimurium, and belongs to the field of food safety technology. The dual-probe detection reagent is composed of a magnetic separation probe reagent solution and a fluorescent nanozyme probe reagent solution, which are packaged separately; the magnetic separation probe reagent solution is used to specifically bind to Salmonella typhimurium and separate and enrich the test sample; the red fluorescent nanozyme probe reagent solution is used to specifically bind to the Salmonella typhimurium after separation and enrichment, and generate a Salmonella typhimurium concentration-dependent colorimetric signal and a fluorescent signal. The dual-probe detection reagent of the present invention has a short detection time and high detection sensitivity for the detection of Salmonella typhimurium, and has good specificity for common model strains. The present invention has a high specific surface area and excellent peroxidase-like activity, which enhances the high-sensitivity capture efficiency; the dual-modal signals of the present invention verify each other, play an internal proofreading role, and the detection results are accurate.

The invention provides a red fluorescent carbon nanodot as well as a preparation method and application thereof. The preparation method of the red fluorescent carbon nanodot provided by the invention comprises the following steps: weighing 0.1-2.8 g of 1, 8-diaminonaphthalene solid, dissolving the 1, 8-diaminonaphthalene solid in 20mL of phosphoric acid, and magnetically stirring to dissolve the 1, 8-diaminonaphthalene solid; transferring the solution into a hydrothermal kettle, carrying out hydrothermal reaction for 6-26 hours under the condition of 120-300 DEG C, and cooling the reaction kettle to room temperature in a natural environment after heating is finished; purifying by using a column chromatography, and taking absolute ethyl alcohol as a washing solvent to obtain a pure carbon dot solution; and finally, evaporating the ethanol solvent by adopting a rotary evaporator, and drying to obtain pure carbon nanodot solid powder. The carbon dot solution can emit bright red fluorescence under the excitation of xenon lamp light with the wavelength of 380-550 nm. The method has a wide application prospect in the fields of time-resolved imaging, advanced information encryption, anti-counterfeiting and the like.