32results about How to "Reduce screening costs" patented technology

The invention relates to a codon optimization method for improving the protein expression quantity of a target gene in a plant, and belongs to the technical field of gene engineering. The invention provides a codon optimization method for improving the protein expression quantity of a target gene in a plant, which comprises the step of replacing the third basic group of a codon of a target protein coding sequence with C or G to obtain an optimized target protein coding sequence. The method has effectiveness and universality in plants, and research shows that after codon optimization of the method, the protein expression quantity of target genes in a plant protein transient expression system and a transgenic plant is increased by several times to dozens of times. According to the production application of the functional protein taking the plant as the bioreactor, the yield of the target protein can be increased, and the protein purification cost can be reduced; according to the application of the method in preparation of the transgenic plant, the expression quantity of the target gene can be increased, so that the target character of the transgenic plant is enhanced, and the screening cost of the high-expression transgenic plant is reduced.

The invention relates to a plastic color master batch screening and impurity removing system and relates to the technical field of plastic color master batch production, the screening and impurity removing system comprises a machine body, a drying and screening mechanism and a scrap iron removing mechanism, and the drying and screening mechanism comprises a conveying belt arranged on the machine body and used for conveying color master batches; the flattening and heating assembly is used for flattening the color master batches and primarily heating the color master batches; the blowing drying assembly is used for blowing hot air to dry the color master batches and removing light impurities in the color master batches, and the scrap iron removing mechanism is used for removing scrap iron in the color master batches dried by blowing the hot air; and the screening assembly is used for screening the color master batch with the scrap iron removed to obtain the color master batch with the required particle size. According to the color master batch production line, color master batches are uniformly spread on the conveying belt through the spreading heating assembly, the air blowing drying assembly is started to dry and clear light impurities at the same time, the scrap iron removing mechanism is used for removing scrap iron, and finally the color master batches meeting the requirements are obtained through screening of the screening assembly, so that the finished product quality of the color master batches is improved.

The invention relates to the technical field of computer system development, and discloses a worker cardiovascular and cerebrovascular risk grading evaluation method based on prior knowledge, comprising the following steps: S1, generating a unique code; s2, judging whether a miner needs to be evaluated or not; obtaining primary screening information for the to-be-evaluated objects; s3, judging whether the miner meets the standard or not; if yes, there is no risk; entering S6; otherwise, entering S4; s4, obtaining secondary screening information and a secondary health score; s5, judging whether the risk is abnormal or not, if not, recording the risk as low risk, and entering S5; if not, entering S6; S5, obtaining third-level screening information and a third-level health score; s6, determining whether there is an abnormality, and if there is no abnormality, recording the risk as a middle risk; otherwise, refusing to go down the well and marking the miner health risk level as a high risk; s6, downhole operation is allowed, and the risk level is marked; S6, downhole operation is allowed, and the risk level is marked; through three times of screening, the screening speed is increased, and the screening cost is reduced.

The invention discloses a high-throughput screening method and device for antioxidant polypeptides, and the method comprises the following steps: (1) collecting polypeptides to construct a polypeptide data set which comprises antioxidant peptides, non-antioxidant peptides and random peptides; (2) encoding polypeptides in the polypeptide data set, extracting features, forming vector representation, and dividing into a training set and a test set; (3) training the learning model by adopting the training set and the test set to obtain a prediction model of the antioxidant polypeptide; and (4) substituting to-be-screened polypeptide sequences into the prediction model in batches, and outputting the antioxidant probability of the polypeptide by the prediction model. According to the method and the device, the oxidation resistance of the polypeptide can be quickly predicted in a high-throughput manner, and meanwhile, relatively high accuracy and a model Morse correlation coefficient are ensured.

The invention discloses an MBTD1 gene molecular marker related to the body weight and body size of a goose and application of the MBTD1 gene molecular marker. The molecular marker is located at the 6290111th site of the 18th chromosome of the goose, and the site polymorphism is C or A. The polymorphic site is remarkably related to the body weight and body size characters of the geese, can accurately judge the final change of the body weight and body size in the future development process of the geese, can be used for early screening of the body weight and body size characters of the geese, greatly reduces the screening cost, accelerates the genetic breeding process, effectively improves the breeding efficiency, and has broad application prospects. The method has high economic application value and scientific research value.

The disclosed embodiment discloses a method and device for filtering business data based on a language model, the method comprising: inputting the data to be filtered belonging to a general field into a first language model corresponding to the general field, obtaining a first group of occurrence probability values ​​of at least one word in the data to be filtered; inputting the data to be filtered belonging to the general field into a second language model corresponding to a predetermined business field, obtaining a second group of occurrence probability values ​​of at least one word in the data to be filtered; determining a first score value of the data to be filtered according to the first group of occurrence probability values; determining a second score value of the data to be filtered according to the second group of occurrence probability values; determining whether the data to be filtered is business data belonging to the predetermined business field according to the first score value and the second score value. The disclosed embodiment is conducive to reducing the cost of filtering business data, and is conducive to improving the efficiency of filtering business data, and thus is conducive to improving the training efficiency of the language model corresponding to the predetermined business field.

The present invention discloses a multimodal fusion emotional disorder detection device and method based on driving tasks, in order to solve the problems of high labor cost, low detection efficiency and low accuracy of existing emotional disorder detection when performing emotional disorder detection on employees in special positions. Specifically, it includes a simulated cockpit, a data acquisition unit, a data processing unit and a power supply unit; the simulated cockpit is used to simulate a real driving environment for the person being tested; the data acquisition unit is used to collect the brain data, sound data, eye movement data and facial expression pictures of the person being tested; the data processing unit is respectively electrically connected to the microphone, infrared light group, infrared light camera, 3D depth laser camera, visible light camera and electrode probe contained in the data acquisition unit, and is used to process the brain data, sound data, eye movement data and facial expression pictures; the power supply unit is respectively electrically connected to each component of the data processing unit and the data processing unit.

The invention relates to the technical field of aluminum powder screening and feeding, and provides an aluminum powder screening and feeding system and method for acrylic plate casting production, the aluminum powder screening is formed by completely utilizing wind power, the aluminum powder screening precision is better, the screening range is wider, the adjustability in the screening process is more flexible, and the practicability is better. The aluminum powder screening environment is good in isolation performance relative to the outside, the self-oxidation reaction in the aluminum powder screening process can be effectively reduced, the cyclic utilization rate of inert gas is higher, the screening cost can be further reduced, the aluminum powder screening device comprises a main body box, a cyclic screening device and a main body support, and the cyclic screening device comprises an annular cylinder; the annular cylinder is fixedly connected to the main body support, a blocking block is fixedly connected to the interior of the annular cylinder, the annular cylinder is communicated with an outer discharging cutting pipe, a feeding cutting pipe and a discharging cutting pipe, the blocking block is located in the portion, between the outer discharging cutting pipe and the feeding cutting pipe, of the annular cylinder, a circulating pump is installed between the outer discharging cutting pipe and the feeding cutting pipe, and the feeding cutting pipe is communicated with an air adding pipe.

The invention discloses a haplotype molecular marker related to cotton fiber strength and application of a detection primer of the haplotype molecular marker, and relates to the technical field of plant molecular biology and genetic breeding. The haplotype molecular marker is located in 112, 985, 431-112, 990 and 059bp regions of A06 chromosome of a cotton reference genome, a haplotype block is formed by nine closely linked SNP (Single Nucleotide Polymorphism) sites, the incidence relation between three haplotypes Hap1, Hap2 and Hap3 in the block and fiber strength is defined, and a new molecular target is provided for cotton fiber quality breeding. Compared with a single SNP marker, the haplotype molecular marker provided by the invention has higher stability and phenotype prediction accuracy under a complex genetic background. Genetic typing can be carried out in the cotton seedling stage based on the marker, fiber maturation does not need to be waited, the breeding period is greatly shortened, and the field screening cost is reduced.

The invention relates to a diagnosis and treatment data management and collaborative diagnosis and treatment method for diabetic retinopathy, which is applied to a medical care terminal, and comprises the following steps: in response to successful login of a user, displaying a homepage of the medical care terminal; skipping to a medical record auditing page under the condition that the user identity is a medical worker and a request for viewing the medical record auditing page is received; the medical record auditing page is used for displaying the medical record data with the marked auditing state; the medical record data is uploaded by a patient end, detection equipment and / or a hospital information system; when a selection operation on the target medical record data whose auditing state is to be audited is received, displaying the target medical record data in response to a preview operation triggered through a preview component; and when a selection operation on the auditing passing component is received, updating the auditing state of the target medical record data to be auditing passing. Therefore, by means of unified state marking and medical record data summarization, medical record state chaos caused by operation habit differences is reduced, and the problems that medical data are scattered and difficult to integrate are solved.

The application discloses a kind of temperature-resistant water-soluble monomer design methods based on generative artificial intelligence.The method comprises the following steps: constructing polymer thermal performance dataset, training quantitative structure-property relationship prediction model;Adopt generative artificial intelligence strategy, by the structure deconstruction and recombination of existing temperature-resistant monomer and water-soluble monomer, generate massive virtual monomer library;Build water-soluble evaluation index considering solubility parameter, oil-water partition coefficient and hydrogen bond number;Combined with synthesis accessibility score, multi-objective high-throughput screening is carried out on virtual monomer library.The application realizes the synergistic optimization and high-throughput screening of the temperature resistance and water solubility of candidate monomers, solves the problems of limited types of existing temperature-resistant water-soluble monomers, mainly relying on experience trial and error in research and development, and low screening efficiency, especially the lack of unified and calculable evaluation index for water solubility, which makes it difficult to optimize and screen the temperature resistance and water solubility as constraints in the process of artificial intelligence aided design.

The invention relates to a Mini-LED / Micro-LED full-color display device based on a photonic crystal and a preparation method of the Mini-LED / Micro-LED full-color display device, and the Mini-LED / Micro-LED full-color display device comprises a driving substrate which is provided with a driving circuit; the light-emitting units of at least three colors are bonded to the driving substrate, each light-emitting unit is prepared by processing a blue light Mini-LED / Micro-LED chip, and each light-emitting unit comprises a buffer layer, an n-GaN layer, a blue light multi-quantum well layer and a p-GaN layer which are sequentially stacked; each light-emitting unit further comprises a control electrode, and the control electrode comprises a p-type electrode layer and an n-type electrode layer; each light-emitting unit can also be provided with a green photonic crystal structure or a red light body structure which penetrates through the buffer layer and extends to the n-GaN layer to form a green light-emitting unit or a red light-emitting unit, and the light-emitting unit without the photonic crystal structure is a blue light-emitting unit; the three adjacent light-emitting units arranged in the array include a red light-emitting unit, a green light-emitting unit and a blue light-emitting unit.

The invention discloses a hard carbon screening method based on a water washing mode, which comprises the following steps: finely crushing a carbon material to be treated to obtain carbon powder particles with the D50 particle size of less than 15 microns, putting the carbon powder particles into a screening net frame, putting the whole screening net frame into an ultrasonic machine, adding deionized water into the ultrasonic machine, keeping an ultrasonic working state, and carrying out ultrasonic treatment on the carbon powder particles to obtain carbon powder particles with the D50 particle size of less than 15 microns; and screening the carbon powder smaller than the aperture of the mesh screen out of meshes of the mesh screen, collecting a carbon powder suspension in the ultrasonic machine, standing, removing a supernatant solution, and drying to finally obtain the carbon powder material. Compared with a traditional method in which a screen filtering and screening mode is adopted in a dry environment, and due to generation of static electricity, friction and other reasons, net blocking and low efficiency are prone to occurring in the carbon powder material screening process, the method is carried out in a washing mode, meanwhile, ultrasonic-assisted screening is carried out, carbon powder can be screened out more easily in a deionized water environment, and the screening efficiency is improved. The efficiency is improved, and the screening cost is reduced.

The invention discloses application of an SNP (Single Nucleotide Polymorphism) molecular marker in identification of dairy cows with high lactoferrin content in milk, the SNP molecular marker is located at the 223 site and the 483 site of a nucleotide sequence shown as SEQ ID NO.1 of a dairy cow LTF gene, the polymorphism at the 223 site is C or T, and the polymorphism at the 483 site is C or T. The two SNP molecular markers can obviously influence the activity of a lactoferrin promoter, further influence the expression quantity of lactoferrin, are stable in hereditary character, can accurately judge the final change of the content of lactoferrin in milk produced by dairy cows after the dairy cows are mature in the future, can screen high-quality genotype dairy cow individuals in the early stage, greatly reduce the screening cost and improve the screening efficiency. The breeding efficiency is improved.

The invention relates to the technical field of building material processing and treatment, in particular to a screening system for waste in concrete gravel aggregate, which comprises a rack connected with a conveying material belt; the two rotating rings are coaxially arranged, the rotating rings are rotationally connected with the rack, and a mounting space is reserved between the two rotating rings; a plurality of arc-shaped grooves are coaxially formed in the rotating ring, the two ends of the screening rods extend into the arc-shaped grooves, the screening rods are connected with the rotating ring in a sliding mode, a waste containing cavity is defined by the multiple screening rods, and the screening rods are located above the upper belt face of the conveying material belt; the multiple interval adjusting units are connected with the rotating ring, and the interval adjusting units are connected with the screening rods and used for changing the width of a passing seam between every two adjacent screening rods; the device has the effect of removing the large-particle-size gravel waste from the gravel aggregate with the low screening cost and the high screening efficiency.

The invention relates to the technical field of screening equipment, and particularly discloses an industrial hemp seed grading screening device which comprises a screening box, a screening mechanism and a driving mechanism, the screening mechanism and the driving mechanism are arranged in the screening box, and the screening mechanism comprises a first screen, a second screen, a bottom plate, a rotating shaft and a sleeve. The peripheral side of the bottom plate is connected with the first screen through a second screen, a screening groove is formed in the first screen, a screening space is formed between the first screen and the bottom plate, hemp seeds to be screened are put into the screening groove, primary screening is conducted on the hemp seeds, and materials obtained through screening enter the screening space to be subjected to secondary screening. Cannabis sativa seeds to be screened are put into the screening groove, primary screening is conducted on the cannabis sativa seeds, materials obtained through screening enter the screening space to be subjected to secondary screening, impurities mixed in the cannabis sativa seeds are removed in a multi-stage screening mode, the screening efficiency of the cannabis sativa seeds is improved, and the screening cost of the cannabis sativa seeds is reduced.

The invention discloses a real-time vehicle end data screening method, device and equipment, a medium and a vehicle. The method comprises the following steps: receiving vehicle end surrounding environment data collected by a vehicle end sensor of a target automatic driving vehicle in real time, and when the vehicle end surrounding environment data accords with a preset image screening rule, taking the vehicle end surrounding environment data as initial screened data; and detecting the initially screened data according to a pre-established large neural network model and a pre-established small neural network model to obtain two detection results of the target shielded vehicle, and when the difference between the two detection results is greater than a preset difference threshold, taking the initially screened data as final screened data. According to the invention, the screening process of all data is completed on line on the vehicle end computing chip, the data does not need to be uploaded to the cloud end for screening, the transmission cost and the storage cost are reduced, manual labeling is not needed, the screening cost is reduced, the original multi-stage long-period data screening process is shortened to be close to real time, and the data timeliness is improved.

The invention discloses a novel energy-saving blanking assembly for glass fiber manufacturing, which is applied to the technical field of blanking assemblies for glass fiber manufacturing, and is characterized in that the novel energy-saving blanking assembly comprises a base; the base is coaxially and rotationally connected with a rotating disc and fixedly provided with a rotating driving assembly for driving the rotating disc to rotate, the rotating disc is uniformly and rotationally connected with four sets of screens of hemispherical structures at intervals in the circumferential direction, and the two symmetrical sets of screens synchronously rotate based on a synchronous rotating assembly; a raw material input assembly and an arc-shaped stirring rod are fixedly arranged over the discharging station of the base, wherein the arc-shaped stirring rod is rotationally connected based on a lifting rotating assembly and stretches into the screen to stir raw materials so as to improve the screening efficiency. A discharging conveying line and a screening conveying line are arranged at the positions, under the discharging station and the screening station, of the base correspondingly. The invention has the technical effects of low use cost and good energy-saving effect.

The application provides a method for rapidly screening aptamers based on exonuclease degradation rate, a reaction system with added aptamers and targets, and a control system with only added aptamers, after adding exonuclease, part of samples are taken out every certain time and added into a quenching solution containing a fluorescent dye, the fluorescent intensity is detected and the relative fluorescent intensity of the reaction system and the control system is compared, and the binding capacity of the aptamers and the targets is indirectly represented. The application can qualitatively detect the affinity of multiple groups of aptamers in a high-throughput and large-batch manner, greatly shortens the screening period, reduces the cost, and is beneficial to subsequent quantitative detection.

This invention relates to the field of biomedical detection technology, specifically to plasma circulating microbial biomarkers for early screening of gastric cancer and their applications. The plasma circulating microbial biomarkers include: *Ralstonia solanacearum*, *Staphylococcus aureus*, *Alternaria metachromatica*, *Porphyromonas gingivalis*, *Lactobacillus reuteri*, *Rhodococcus erythropolis*, *Akkermansia muciniphila*, *Lactobacillus gasseri*, *Bifidobacterium bifidum*, and *Neisseria gonorrhoeae*. This invention screens and, for the first time, combines 10 specific microbial biomarkers with Low Pass technology. WGS technology can achieve detection results at low depths, significantly reducing screening costs while ensuring detection sensitivity, and providing a brand-new solution for early gastric cancer screening.

The invention provides a screening method for rapidly identifying tetracoccus halophilus and application of the screening method, and belongs to the technical field of microorganisms. According to the application, specific screening and identification of the tetragenococcus halophilus are realized, genome extraction and on-machine sequencing of strains are not needed, the screening efficiency is improved, and the screening cost is reduced; based on specific gene amplification of biogenic amine generation key enzyme, screening of strains which do not generate biogenic amine is carried out, so that the screening efficiency is further improved, and efficient screening of industrial excellent-character tetracoccus halophilus strains is realized. By adopting the method disclosed by the invention, the identification of the tetracoccus halophilus and the screening of the tetracoccus halophilus which does not generate histamine and tyramine can be simultaneously carried out, high-throughput detection is realized, the labor cost and the time cost of gene extraction and sequencing are effectively reduced, and the problem that the performance and the quality of traditional fermented food are unstable is solved.

The utility model relates to the technical field of color master batch production, and discloses a high-frequency vibration type screening device for color master batch production, which comprises a screening box and a support frame, a support plate is arranged on the inner side of the screening box, a screening net is arranged at the upper end of the support plate, a vibration box is arranged on the outer side of the screening box, an electric telescopic rod is arranged at the lower end of the vibration box, and a vibration mechanism is arranged in the vibration box; the vibrating mechanism comprises a moving rod, the lower end of the moving rod is fixedly connected with the electric telescopic rod, a pushing block is arranged on the outer side of the moving rod, a guide slope is arranged at one end of the pushing block, a push rod is arranged at one end of the pushing block, and one end of the push rod extends to the lower end of the screening net. The upper end of the vibrating wheel makes contact with the screening net. According to the utility model, the vibrating mechanism is arranged, so that a plurality of groups of screening nets can be driven by one group of vibrating mechanism for screening, the overall energy consumption in the screening process is reduced, and the screening cost is reduced.

The application discloses a blood pressure reducing dipeptide activity prediction method based on XGBoost, and belongs to the fields of food science and biology technology. The method comprises the following steps: firstly, collecting published blood pressure reducing dipeptide sequences and their activity IC 50 values, and constructing a data set; secondly, introducing sequence, physicochemical and amino acid atomic composition features of a peptide segment, and performing feature expression on the dipeptide sequence; thirdly, performing principal component expression on the features of the peptide segment, and performing principal component selection; fourthly, combining the principal components and an XGBoost regression model to construct a prediction model and performing precision evaluation on the model; then, training the model by using all data of an existing dipeptide data set, and realizing model construction; and finally, applying the prediction model to perform activity prediction on unknown blood pressure reducing dipeptide sequences. The prediction method can reduce the complexity of peptide activity prediction, effectively improve the prediction precision, reduce the screening cost, and can be widely applied to blood pressure reducing activity and other activity prediction of dipeptide sequences.

The present invention belongs to the field of micro-nano fluid and biochemical sensor technology, and specifically relates to a micro-nano fluidic chip and a parallel enrichment detection method for biochemical marker molecules, wherein the chip comprises a chip body, and the chip body is provided with a first channel, a plurality of second channels, a third channel and a nanoflow channel, wherein the first channel is provided with a first liquid inlet; each of the second channels is provided with a detection area and is connected to the first channel; the third channel is connected to the second liquid inlet; the nanoflow channel has an ion selection function, one side of the nanoflow channel is connected to the third channel, and the other side is respectively connected to a plurality of second channels. The micro-nano fluidic chip of the present application can realize the simultaneous enrichment detection of dozens or even hundreds of biochemical marker molecules through the parallel second channel design, greatly reducing the cost of disease screening, and providing strong support for early screening of diseases, condition monitoring and treatment effect evaluation.

The present invention discloses a SNP molecular marker related to goose weight and body size and an application thereof. The nucleotide sequence of the molecular marker contains a SNP site at position 61331488 of chromosome 4 of the goose, and the polymorphism of the SNP site is G or A. The polymorphic site is significantly correlated with the weight and body size traits of the goose, and can relatively accurately judge the final changes in the weight and body size of the goose in the future development process, and can be used for early screening of the weight and body size traits of the goose, greatly reducing the screening cost, accelerating the progress of genetic breeding, and effectively improving the breeding efficiency, and has high economic application value and scientific research value.

The invention provides a nucleic acid composition for human papilloma virus nucleic acid detection, a kit and application thereof, and belongs to the field of gene detection. The kit provided by the invention comprises probes corresponding to 18 genotypes of HPV16, HPV18, HPV26, HPV31, HPV33, HPV35, HPV39, HPV45, HPV51, HPV52, HPV53, HPV56, HPV58, HPV59, HPV66, HPV68, HPV73 and HPV82, as well as 17 forward primers and 15 reverse primers corresponding to the 18 genotypes, and further comprises an amplification reaction solution, a negative control, a positive control and a quality control internal reference. The kit provided by the invention can be used for simultaneously detecting 18 high-risk human papilloma viruses in a single reaction, can be used for typing common HPV16 and HPV18, and is simple, rapid, high in specificity and high in sensitivity.

This invention provides an AI-based multi-model collaborative intelligent screening and deep analysis method for multimodal data, comprising: differential preprocessing based on modal differences in multimodal samples, dynamically adjusting preprocessing parameters through sample metadata analysis; evaluating sample data quality using multi-dimensional indicators to obtain high-value data; using an importance and diversity coupled optimization strategy to screen high-value data to obtain effective samples; performing modal alignment on the screened samples to complete cross-modal feature fusion and generate a unified fused feature vector; performing multi-dimensional deep analysis on the fused feature vector to mine inter-modal correlation information, and combining domain transfer learning to achieve result generalization; evaluating the analysis results in real time based on preset indicators, and dynamically adjusting the core parameters of the entire process based on the evaluation results. The beneficial effects of this invention are: solving the problems of high screening cost, low accuracy, poor fusion effect, weak analytical capability, poor interpretability, and inflexible deployment in existing technologies.

This invention discloses a method and system for recommending bank points malls based on multi-dimensional user data analysis. The method constructs an intelligent recommendation closed loop through a six-step core process: First, it organizes users' regular consumption data, achieving multi-dimensional collection, cleaning, labeling, and dynamic updates; second, it collects and filters spatiotemporal hotspot data of the user's region to accurately match offline scenario needs; third, it integrates multi-channel online hotspot data, quantifying popularity and timeliness; fourth, it binds the two types of hotspot data with points mall products by weight; fifth, it calculates and dynamically adjusts the correlation between products; and finally, it generates a default recommendation list based on the hotspot correlation and dynamically switches to related product recommendations based on real-time user interaction behavior. This invention solves the problems of single recommendation dimensions, insufficient accuracy, and delayed timeliness in existing technologies. By integrating multi-dimensional data and a dynamic feedback mechanism, it significantly improves the accuracy of points mall recommendations, user interaction experience, and points redemption conversion rate.

The invention relates to the technical field of tobacco agriculture, in particular to a method for screening tobacco varieties with high flavonoid content based on Multiplex 3, and the Multiplex 3 is used for detecting the flavonoid content of tobacco leaves, so that the tobacco varieties with the tobacco leaves with high flavonoid content are screened. The screening method provided by the invention can accurately, losslessly and quickly identify the tobacco single plants with the tobacco leaves with high flavonoid content, and compared with the prior art, the method provided by the invention has the advantages of simplicity and quickness in detection, accuracy, losslessness, low destructiveness, no application scene limitation, safety and reliability.

This invention relates to the field of agricultural breeding technology, specifically to a method for screening nitrogen-efficient rice mutants. The method includes: providing a rice mutant population subjected to space-induced mutagenesis; subjecting the rice mutant population to hydroponic stress treatment with chlorate solution before the three-leaf stage; measuring the seedling length of the treated group and the control group, and calculating the seedling length inhibition rate; and screening nitrogen-efficient candidate mutants based on the seedling length inhibition rate. This invention also relates to nitrogen-efficient rice mutants obtained by the method and their application in nitrogen-efficient rice breeding. The method of this invention is simple to operate, has a short cycle time, and low cost, enabling rapid and accurate screening of nitrogen-efficient materials from large-scale populations, which is of great significance for cultivating new crop varieties with efficient nitrogen fertilizer utilization.