313 results about "Controlled experiment" patented technology

The invention provides a model ship based autonomous navigation control simulation system and method of an under-actuated unmanned ship. The whole system is arranged on a model ship, and the model ship is arranged in a simulated navigation channel; the system comprises an environment sensing sub system, a path programming sub system and a motion control sub system; the environment sensing sub system collects the navigation state of the model ship and simulates environment factor information; according to the navigation state of the model ship and the simulated environment factor information, the path programming sub system carries out navigation programming to obtain the tracking route, the set speed and the set course; and the motion control system combines a course tracking model, a path tracking model, the route deviation, the course deviation and the speed deviation to calculate the rudder angle and propeller rotating speed instruction needed in next navigation of the model ship and control a steering engine and a propeller. According to the invention, simulation experiments are carried out on the model ship, an instance is provided for operation and control experiments of large ships, important guarantee is provided for safe navigation of large ships in inland rivers, and the system reduces the difficult and cost of experiments of the large ships.

The invention relates to enterobacter ludwigii BG10-1 and application thereof in biological prevention and control over aspergillus flavus. The enterobacter ludwigii BG10-1 is preserved in China Center for Type Culture Collection (CCTCC) on January 7, 2016, the preservation number is CCTCC NO: M 2016014, and the classification name is EnterobacterLudwiggi BG10-1. The enterobacter ludwigii BG10-1 is obtained by being separated from peanut pods produced in Babu Town, Hezhou City, Guangxi Province. Through indoor confrontation and antagonism experiments, living body bacteriostasis and detoxification experiments and field prevention and control experiments, it is found that the strain is high in bacteriostatic capacity on the aspergillus flavus, easy to culture, free of contamination and safe to environment. By applying microbial fertilizer of the enterobacter ludwigii BG10-1, contamination of the aspergillus flavus to peanuts can be effectively prevented and controlled.

The invention discloses a method for obtaining germination effective symbiotic fungus of Cymbidium bicolor seeds, which includes: using dead twigs, fallen leaves, bark, moss, humus and the like around an original habitant of Cymbidium bicolor as culture medium, subjecting the culture medium and the seeds of Cymbidium bicolor to ex-site symbiotic germination to induce the seeds to germinate and generate protocorms; sterilizing the surface of each obtained protocorm, culturing with thy artificial culture medium under the sterile condition, inducing endophytic fungus in the protocorms to grow, purifying the fungus to obtain a pure colony after mycelia appears; and subjecting the obtained fungus and the seeds of Cymbidium bicolor to symbiotic germination culturing, carrying out a control experiment to check the effectiveness of the obtained fungus to germination of the seeds of Cymbidium bicolor, screening germination effective symbiotic fungus for the seeds of Cymbidium bicolor, and subjecting the fungus to molecular identification and storage. The method is simple to operate, singe variety of fungi can be obtained, massive and troublesome screening is not needed, and a new way of using Cymbidium bicolor seeds and fungus to symbiotically germinate to culture seedlings is opened.

The invention provides a modified gold nanorod. The surface of the modified gold nanorod is wrapped by gold nanocluster which is wrapped by bovine serum protein (BSA), so as to form a novel nanometer composition. The composition is exposed under the irradiation of near infrared light and used for exploring the photothermal performance and photothermal stability. After irradiation of near infrared light for many times, the optical property and shape of the gold nanocluster-gold nanorod composition have no obvious change, and the temperature is obviously increased. As a comparison, the identical gold nanorod and the bovine serum protein wrapped gold nanorod are sequentially used as stability control experiments. In addition, the photothermal performance and the glue stability of the gold nanocluster-gold nanorod composition have extremely good reproducibility. Therefore, the nano composition capable of improving the photothermal property and the photothermal stability is very suitable for further biological applications, such as remote sensing, bioimaging and photothermal therapy.

The invention discloses a multichannel microfluidic-solid phase extraction-mass spectrum combined device and a preparation method. The combined device comprises a microfluidic chip and a mass spectrometer, wherein the microfluidic chip is provided with upper and lower layers of channels; the upper layer of channel is a cell culture channel; the two ends of the upper layer of channel are provided with a vertical hole and a horizontal hole respectively; the lower layer of channel is a chemical oxygen uptake channel; the two ends of the lower layer of channel are provided with a plurality of groups of vertical holes respectively, and the upper and lower layers of channels are connected through a layer of PDMS (Polydimethylsiloxane) membrane; C18 spherical particles are filled on one side of the upper layer of channel to form a filling column; the horizontal hole of the upper layer of channel is connected with the mass spectrometer. The physiological behaviors of cells under different oxygen environments can be simultaneously observed, and control experiment, multi-concentration gradient parallel stimulation and multi-region detection can be realized at one time. Through separation and enrichment of the solid-phase extraction chip, mass spectrum real-time detection is realized, cell metabolites can be more intuitively and more accurately detected, and a theoretical basis is provided for research of tumor cell hypoxia.

The invention discloses a preparation method of a metal polyphenol vesicle material with a micrometer / nanometer multilayer composite structure. The metal polyphenol vesicle material with the multilayer composite structure is obtained by etching polyphenol by taking a metal organic framework compound serving as a template. The precise control on an internal structure of a vesicle and the surface roughness of the vesicle is realized through controlling experiment parameters such as etching time and a pH value. The functionality of the obtained vesicle material is also greatly enriched by introducing a polyphenol structural unit to an assembly system, and the preparation method is favorably applied to aspects such as catalytic reaction and drug delivery.

The invention provides a high-temperature and high-pressure volume expansion and shrinkage tester of oil well cement, and belongs to the field of volume expansion and shrinkage test devices of the oil well cement. The tester comprises a high-temperature and high-pressure kettle, a temperature control system, a pressure control system, a controller and a computer data processing system. The tester can simulate the volume shrinkage rate and the volume expansion rate of the oil well cement in a vertical well and a horizontal well at a maintenance temperature under a maintenance pressure, and record a temperature-pressure curve and a time-expansion / shrinkage rate curve. The tester provided by the invention has the advantages of adjustable experiment pressure, automatically-controlled experiment temperature, real-time display of the experiment pressure and the experiment temperature, real-time display of the volume expansion / shrinkage curve of a cement mortar, simple experiment operation, automatic output and preservation of experiment results, automatic generation of an experiment report, reasonable structure and layout, and concise appearance.

The invention discloses a zirconium-base metal organic frame composite material and a preparing method and application thereof. By controlling experiment conditions, a UiO-66-NH2 metal organic frame material with the grain diameter of 100 nm is obtained, and serves as a loading matrix, a signal molecule tri-(2,2'-dipyridyl) ruthenium dichloride is embedded in a pore way structure regularly and evenly distributed, a Ru-UiO-66-NH2 material is obtained, loading of silver nanoparticles is conducted through the high specific surface area of the Ru-UiO-66-NH2 material, and the obtained Ru-UiO-66-NH2material is applied to detection of small-molecule hydrogen peroxide with the electrogenerated chemiluminescence detection technology. Through the method, interference of background signals can be avoided, optical signals are stable, and the sensitivity is high.

The invention relates to a method of synthesizing porous charcoal containing nitrogen, sulfur and other hetero atoms based on Schiff base chemistry and by utilizing an in-situ solid phase process. A Schiff base reaction between an amino-containing aromatic ring compound (melamine, sulfanilic acid, and the like) and an aromatic-ring-containing aldehyde (terephthalaldehyde, 1,3-benzenedialdehyde or 4,4'-biphenyldicarboxaldehyde) is utilized to generate a nitrogen-containing sulfur-containing polymer. Through a gas-solid phase reaction between a reducing atmosphere such as carbon oxide compounds generated in a pyrolysis process of the polymer and lithium oxide, carbonate is generated in an in-situ manner and adopted as a template for preparing the charcoal material, and acid washing is performed to remove the template to obtain the honeycomb porous charcoal material containing nitrogen, sulfur and the like. According to the method, the method is simple to operate, equipment is simple, and the template is generated by an in-situ reaction, thus further preparing the porous structured charcoal material. Through regulating and controlling experiment parameters, the multistage porous charcoal material which contains nitrogen, sulfur and other hetero atoms, which has controllable morphology and an adjustable pore channel structure can be prepared.

The invention discloses an establishment method of an RTDS-EMS (real time digital simulator-energy management system) system-level closed-loop control experiment simulation platform. The method comprises the following steps: establishing a simulation model of an equivalent station on a real-time digital simulator RTDS system; performing real-time digital simulator RTDS simulation by utilizing the simulation model of the equivalent station; drawing an actual device wiring diagram corresponding to the equivalent station in an energy management system EMS; mounting a network communication interface card GTNET, configuring network running parameters of a front-end system FES; designing and developing a protocol converter to realize information intercommunication between the real-time digital simulator RTDS and the energy management system EMS; virtualizing a plurality of remote terminal units RTU, and controlling the connection between the virtual remote terminal unit RTU and the energy management system EMS to simulate inconsistent sampling time at different control centers in an actual electric network. The method realizes RTDS-EMS system-level closed-loop control.

The invention discloses a supporting and protecting device for a high-speed wind tunnel plasma flow control experiment. The supporting and protecting device for the high-speed wind tunnel plasma flow control experiment comprises an aerofoil-profile insulation protecting and supporting device and an electromagnetic shielding and protecting device; the aerofoil-profile insulation protecting and supporting device comprises a side wall pivoted window structure and an attack angle mechanism supporting platform; the electromagnetic shielding and protecting device comprises multiple layers of shield high-voltage leads and a grounding copper foil wide band. The supporting and protecting device provided by the invention can be used for guaranteeing the insulation among a model, a side wall pivoted window and a supporting platform and the insulation between fixing screws and ear sheets, meanwhile also guaranteeing the intensity of the side wall rotary window and the supporting platform, additionally enabling induction electromagnetic fields to be attenuated layer by layer by adopting multiple layers of shielding high-voltage leads, meeting the safety of voltage and electromagnetic shielding requirements of measurement and control instruments, and reducing the induced voltage caused by the transmission lead radiation electromagnetic fields greatly by adopting copper foil broad band ground connection.

The invention discloses O / W nano-emulsion and a low-energy-consumption preparation method thereof. The O / W nano-emulsion comprises the following components: 2-27 parts of an oil phase, 1-18 parts of a nonionic surfactant and the balance being water. The O / W nano-emulsion is small in particle diameter, narrow in distribution, good in stability and free of layering phenomenon after being placed for three months. According to the method, the O / W nano-emulsion with the different particle diameters can be prepared by adjusting and controlling experiment conditions, and the nano-emulsion with the proper particle diameters can not damage healthy skin and cells.

The invention discloses a single-leg impact control experiment platform for a robot. The single-leg impact control experiment platform comprises an integrated controller, a robot leg lifting device, a test bed bracket, a static loading device, a six-dimensional force sensor and a five-dimensional force measurement platform, wherein the test bed bracket comprises a test bed bracket base and a test bed bracket vertical column; the integrated controller is fixed on the test bed bracket base; the robot leg lifting device is fixed on the test bed bracket; the static loading device is fixed on the robot leg lifting device; the six-dimensional force sensor is arranged between the lifting device and a robot body; and the five-dimensional force measurement platform is fixed on the ground below the six-dimensional force sensor. The single-leg impact control experiment platform can obtain indexes such as a dynamic response characteristic of single-leg popping motion under different constant loads and the structural stability of a single leg under the action of large short-time impact. The platform is simple in structure and runs stably and reliably.

The invention relates to a control analysis method for inverters in a grid-connected test power supply, and belongs to the technical field of electronic power. The control analysis method for the inverters in the grid-connected test power supply comprises the following steps that (1) the topological structure of the inverters in the grid-connected test power supply is determined; (2) the model of an inversion circuit is constructed; (3) the control strategy of the inversion circuit is determined; (4) quasi PR control analysis is performed; (5) the transfer function of a quasi PR controller is discretized, modeling of the discretized PR controller is performed through Simulink and then various control parameters of the inverters are calculated; and (6) a 30KW hardware-in-the-loop grid-connected test power supply dual-core control experiment platform is established based on dSPACE and the correctness of the control model is verified. According to the method, PR control is adopted, and the specific frequency can be accurately tracked by PR control in comparison with PI control so that the gain of the frequency is increased and the steady state error of PI control is eliminated.

The invention provides a crop Pythium biological control bacillus subtilis strain and belongs to the biotechnological sphere. The invention relates to a crop Pythium bacillus subtilis strain and its biological crop preserved number is CGMCC1732. The said strain can reduce the growth of Ralstonia solanacearum and the biological control experiment indicates that it can prevent and cure the Granville wilt. Simultaneously the invention also provides an antagonistic protein blend obtained from the said strain and the blend has higher application value in crop Pythium biological control.

The invention provides a microbe-wilt bacterium preventing ANTI-8098A and the culture medium, culture method and biology application thereof. In particular a wilt bacterium preventing strain ANTI-8098A is provided, which is preserved in the Deutsche Sammlung von Mikroorganismen und Zellkulturen(DSMZ), with the preservation number being DSM ID01-100, the classification designation of the microbe being Bacillus cereus. The wilt bacterium preventing microbe collecting method, screen method, ferment production method and the culture medium thereof are provided, the supernatant containing the wilt bacterium preventing microbe or its ferment liquid, the biological pesticide and biological bactericide germicide containing its metabolic product are also provided. The prevention and cure effect of the wilt bacterium preventing microbe and the biological pesticide and biological bactericide germicide on the wilt bacteria of various kinds of plants in the field control experiment is over 80%, in addition, the quality and the output of the treated fruits are increased.

The invention discloses ectomycorrhizal helper bacteria bacillus pumilus HR10. The classified nomenclature of the ectomycorrhizal helper bacteria bacillus pumilus HR10 is bacillus pumilus, the bacillus pumilus is preserved in CCTCC, the collection number of the bacillus pumilus is CCTCC No: M 2010143 and the preservation date is June 12th, 2010. The bacillus pumilus HR10 is plant growth-promoting rhizobacteria, has direct promoting effect on black tree growth and can promote the growth of rhizipogen luteous of ectomycorrhizal fungi; double inoculation of the bacillus pumilus HR10 and the rhizipogen luteous has obvious growth-promoting effect on pinus thunbergii parl; the bacillus pumilus HR10 has inhibiting effect on pathogenic rhizoctonia of pine nursery stock damping-off disease; and greenhouse preventing and controlling experiments show that the bacillus pumilus HR10 strains can effectively prevent and control the pine nursery stock damping-off disease.

The invention discloses an alfalfa drought tolerance identification method, comprising the following steps: after sterilization on seeds, carrying out a conventional sprouting experiment, after a seedling has 3-4 main leaves, performing thinning and final singling, reserving materials whose plant size and height are roughly consistent, and carrying out a water controlling experiment in a greenhouse; in the 8th-11th day, taking the plants out to count the number of roots of each plant of alfalfa, including the number of main roots, lateral roots, and fibrils on the lateral roots; after processing for 20 d, respectively measuring seedling height, fresh weight of root systems, dry weight of root systems, leaf chlorophyll contents, stomatal conductance, leaf free water content, leaf surface bound water content, proline content and root volume of each processing group; performing data reduction, calculating average values, and calculating a drought tolerance coefficients and a comprehensive drought tolerance value of each variety; and determining salt tolerance of the varieties according to the comprehensive drought tolerance value. The method performs multivariate statistical analysis on agronomical characters and indexes of an alfalfa seedling stage, so as to perform comprehensive judgement and evaluation on the drought tolerance of alfalfa.

The invention relates to the technical field of wheat abiotic stress identification, in particular to a wheat drought identification method. A method for identifying the drought of wheat comprises thefollow steps of: a) carrying out a drought control experiment of wheat in a greenhouse by adopting a pot experiment method, wherein the drought grade are suitable, light drought, medium drought, severe drought and special drought; b) continuously acquiring wheat images of different drought grades by using a single-lens reflex camera, labeling the wheat images, and randomly dividing the data setsinto a training set and a test set; c) extracting image features using convolution operations of Inception_V3, Resnet_50, Resnet_152, which are pre-trained on ImageNet, and training the final classification layer; d) testing the trained depth learning network with the test set, and representing the accuracy of drought stress identification and classification with the accuracy of drought stress identification DSI and drought stress classification DSC respectively. As the wheat phenotypic characteristics are extracted by a depth learn method through acquiring a wheat digital image, the drought stress is identified and classified base on a disaster-bearing body, the drought stress is timely, accurate, lossless, and the wheat phenotypic characteristics are high in accuracy.

The invention discloses a lithium ion battery thermal runaway spreading simulation method and device. The invention relates to a lithium ion battery thermal runaway spreading simulation method and system. The method comprises the following steps: firstly, establishing a lithium ion battery normal heat generation prediction model and a lithium ion battery thermal runaway heat generation predictionmodel; setting a simulation monomer for simulating the lithium ion battery based on a wireless energy transmission principle of a primary side and a secondary side; then, heat generation estimation iscarried out on the lithium ion battery by utilizing the established heat generation model; calculating the heat generation power by utilizing heat generation estimation; the heat generation current is calculated by utilizing the heat generation power of the lithium ion battery; calculating expected values of corresponding parameters of a primary side by taking the calculated heat generation current of the lithium ion battery as a secondary side current demand value; corresponding parameters of the primary side are adjusted to simulate heat generation of the heat generation element; and judging thermal runaway spreading through the obtained surface or internal temperature distribution of the simulation monomer to complete lithium ion battery thermal runaway spreading simulation verification, thereby evaluating the safety of the lithium ion battery system and realizing lithium ion battery module thermal runaway management and control experiment verification.

The invention relates to a method for preparing a polypyrrole / gold nano composite, belonging to the technical field of material, comprising the following steps: uniformly stirring deionized water, surfactant and cosurfactant at room temperature, adding pyrrole in the system, and adding certain concentrated hydrochloric acid to adjust the PH value to 0.8-1.3; adding auric chloride acid solution slowly to react for 3-6h; after the reaction, carrying out demulsification, centrifugation and drying to obtain polypyrrole / gold nano composite particles. The polypyrrole / gold nano composite particles prepared by the invention are in a good dispersion and regular tetrahedron morphology, have good conduct electricity, good electrical conductivity, and are capable of being used in the fields of electrode material, luminescent material, electromagnetic shielding material, anticorrosion paint and the like of secondary battery. Simultaneously, the preparation method has the advantages of simple process, low reaction environmental requirement, and easy to control experiment parameters.

The invention discloses an insecticidal composition and a preparation thereof. The insecticidal composition comprises spirotetramat and one ingredient selected from nitenpyram, chlopyrifos, acetamiprid or imidacloprid. The results of field control experiments show that compared with a single dose of spirotetramat, the insecticidal composition and the preparation has obvious synergistic action.

The invention relates to a method for measuring the contents of total nitrogen and total phosphorus contained in seawater substrate sludge by adopting combined digestion, comprising the following steps of: weighing 1.0 g of air-dried sample screened through a phi 0.5 mm sieve; adding 8 mL of sulfuric acid and 2 mL of hydrogen peroxide, carefully and uniformly shaking, and placing overnight; slowly increasing temperature till the sulfuric acid is smoky; slightly cooling, then adding a plurality of drops of hydrogen peroxide, and continuously heating till the solution is colourless or off-white; slightly cooling, adding water, and heating to boiling; taking down for cooling, nondestructively transferring a digested solution into a 100 mL volumetric flask, adding water, fixing volume, and standing for clarification or filtering by using phosphate-free filter paper; then sucking 10.0 mL of sample solution containing 0.05-1.0 mg of the phosphorus into a 50 mL volumetric flask, adding water to 20-30 mL, carrying out color development and color comparison with a standard solution series under same conditions, and reading absorbance; and carrying out a control experiment by respectively using standard substances, i.e. ammonium sulfate and monopotassium phosphate to measure the contents of the total nitrogen and the total phosphorus which are contained in the seawater substrate sludge. The measuring method has high accuracy and easiness, convenience and fastness for operation and is suitable for batched measurement, thereby enhancing the work efficiency.

The invention discloses an improved rotational-inertia compensation method considering a communication time lag and an acceleration time lag.The problem that when a present wind turbine simulator simulates a large-rotational-inertia wind turbine, instability and vibration occur is solved.The compensation method includes the steps that a wind turbine simulator is tested to determine the rotational inertia of the wind turbine simulator; a wind turbine model simulated by the wind turbine simulator is determined, and the rotational inertia of the wind turbine model is determined; the wind turbine simulator is tested to determine the step length of the communication time lag; a filter is added into a dynamic-torque compensation branch circuit of the wind turbine simulator according to the situation; the parameters of the digital filter are adjusted, and the wind turbine simulator stably runs.By means of the compensation method, the instability problem, caused by the communication time lag and the acceleration time lag, of the WTS is solved, the WTS can stably simulate the large-rotational-inertia wind turbine in the mode that the influence of the time lag is eliminated, and a user is assisted in conducting a control experiment of the wind turbine in the laboratory environment.

The invention discloses a model for evaluating different degradation degrees of meadow grassland and an establishing method and application thereof. The method aims at natural grassland with differentdegradation degrees caused by different utilization degrees of meadow grassland. Through a field control experiment, a field ecology investigation method is adopted. the response mechanism of meadowgrassland degradation to human activities (controlling grazing) is studied;A principal component analysis is made, a matrix through typical correlation and fuzzy mathematics are establsihed; The an indication degree diagnosis method of a degradation evaluation system is established with different utilization degrees, grassland vegetation and soil index systems with different utilization modes anddifferent degradation degrees are screened, indication degrees of different degradation degrees is acquiredand a meadow grassland degradation quantitative evaluation index system indication degree diagnosis method with relatively high scientificity and operability is established. The method has practical significance in establishment of meadow degradation index system evaluation, objective judgment of the degradation condition of meadow and promotion of production and environmental protection of meadow animal husbandry.

The invention relates to a device and method for measuring pitch particle profile control performance parameters. The device mainly comprises a screwed pipe with large drift diameter, a turbulent flow generation tank, a perforation simulating unit and a near-wellbore stratum simulating unit, wherein the turbulent flow generation tank, the perforation simulating unit, the near-wellbore simulating stratum unit, and a columnar rock core to be measured all adopt cylinder structures and have same end face diameters; all end faces are connected end to end in sequence and are clamped for fixing by a rock core clamp holder; a profile control liquid passes each part in sequence and finally enters the columnar rock core to be measured smoothly. The device and the method are safe and reliable, can relatively truly simulate the movement state of pitch particles before and after entering the columnar rock core, efficiently overcome the defects that the particles are relatively seriously blocked in a rock core fracture surface and can not be injected, and realize research and effect evaluation of indoor profile control experiments using the pitch particles.

The invention discloses a Pseudomonas putida strain for bio-control of Tobacco mosaic virus, wherein the strain code is A3; the strain is preserved in the General microbial center of China Committee for Culture Collection of Microorganisms on 7 September 2011, and the preservation number of the strain is CGMCC No.5231. The strain can restrain invasion of the Tobacco mosaic virus. The bio-control experiment shows that the Tobacco mosaic virus can be prevented and treated. Simultaneously, the invention also provides a mixture of active small molecule substances obtained from the strain, and themixture has high application value in the respect of prevention and treatment of the Tobacco mosaic virus.

The invention discloses a method for fast identifying harmful algae. The method is characterized by comprising the following steps of: a, preparation of experimental algae f / 2 and derivative culture media of the experimental algae; b, design and verification of primers; c, obtaining of 18s rDNA fragment of the experimental algae; d, optimization and propagating of (polymerase chain reaction) PCR; e, control experiment of simulated enzyme cutting and practical enzyme cutting; and f, identification of the harmful algae by using restriction fragment length polymorphism (RFLP). As a molecule ecological means for identifying the harmful algae, the method can serve as the supplementary means and auxiliary means of the conventional identification methods. The method establishes a characteristic map based on FELP, standardizes the whole flow, and is favorable for initially identifying the harmful algae fast, easily and conveniently and pre-alarming the outbreak of the red tide of phytoplankton.

The invention discloses a teaching experiment system and an experimental method suitable for communication type specialties. The system comprises an experimental apparatus, communication equipment, an application server and a Web server, wherein control programs of the experimental apparatus and the communication equipment are installed on the application server for transmitting control instructions to the experimental apparatus or the communication equipment or receiving data information returned by the experimental apparatus or the communication equipment; the Web server bilaterally exchanges data with the application server through a local area network and bilaterally exchanges data with a client through the local area network or Internet; system management software is installed and a knowledge database is stored in the Web server for providing the functions of inquiring and browsing a webpage and observing and controlling experiments in real time for learners; and a plurality of relational tables of curriculum knowledge, experimental apparatus function information, communication equipment structure function information, signal protocol information and the like are established in the knowledge database, so that the inquiry requirements of the learners can be met in real time.

The invention discloses a method for preparing a molecular device with surficial biomolecules removed and based on graphene electrodes. The method includes: (1) preparing a graphene transistor device array, wherein the conducting channel in the graphene transistor device array is the grapheme, a channel is arranged on the grapheme, DNA sequence connecting parts with lengths of 1-10nm are arranged on the channel at an interval and perpendicular to the sources and the drains in the graphene transistor devices; (2) soaking a molecular connecting device of the graphene electrodes in TritonX-100 for 0.5-3h; and connecting a designed DNA sequence into nano gaps to obtain the DNA unimolecular connecting device. The prepared unimolecular connecting device based on the graphene electrodes is used for electrical signal detection, a control experiment is set simultaneously, a detection result proves that the biomolecules on the surface of the molecular device of the graphene electrodes can be removed effectively, and the detection accuracy can be improved.