184results about How to "Potential for application" patented technology

The invention discloses a Doppler anemometer laser radar structure and detecting method based on F-P etalon, which is characterized by the following: the optical path contains Nd: YAG laser to output two beams of laser, wherein one beam is launched towards sky through two-dimensional scanning unit of plane reflector; the other beam laser intersects the input end of two-in-one optical fiber coupler through optical fiber; the optical fiber receiving port is loaded at the focus point of telescope cylinder with the optical fiber intersecting the input end of two-in-one optical fiber coupler; the output end of two-in-one optical fiber coupler connects collimating mirror through optical fiber, whose optical path loads color filter, beam splitting piece at 4:1 transparent-reflect rate, F-P etalon; one rectangle reflecting lens is set in the reflecting optical path of transparent optical path and beam splitting piece of etalon separately with one photon count detector setting on two sides of reflecting surface of each rectangle reflecting lens; the output end of photon count detector intersects data gathering and disposing equipment; the invention adopts double-brink technology to detect the layout of tropospheric atmospheric wind field directly.

Provided are a preparation method and application of PDMS polymer chips of arc-shaped concave apertures. The method includes the steps of: making use of the soft etching technology to make a PDMS channel chip template; producing PDMS film, sealing the PDMS channel chip template with the PDMS film to seal with a glass plate, connecting the bottom with gas by a metal pipe, modifying the apparatus surface; pouring the uncured PDMS polymer solution into the apparatus, feeding the gas, heating to cure the PDMS polymer solution, and peeling the PDMS chip. The PDMS chip after surface modification can be used for three-dimensional culture of cells. The method does not require expensive etching equipment, has the advantages of simple and rapid operation, low experiment cost, no organic reagents, and environmental protection, and can be integrated with other technologies.

The invention discloses a method for preparing ring-shaped bismuth oxyiodide (BiOI) microspheres and relates to a photocatalyst. The method comprises the following steps of: dissolving Bi(NO3)3 into alcohol to obtain a solution A, and mixing KI with oleic acid to obtain a solution B; and mixing the solution A with the solution B to obtain a mixed solution, stirring, then pouring the mixed solution into an autoclave, performing a hydrothermal reaction on the mixed solution, cleaning, filtering and drying to obtain rufous ring-shaped BiOI microspheres. According to the method, the Bi(NO3)3 and the KI are used as raw materials for preparing the ring-shaped BiOI microspheres in the mixed solution of alcohol and oleic acid by using a low-temperature hydrothermal one-step method. Compared with BiOI microspheres of other shapes, the ring-shaped BiOI microspheres are defined by a group of nano-sheets which are parallel and arranged into a circle, and the ring-shaped BiOI microspheres have a porous structure, so that the adsorption performance is improved, and then the photo-catalytic activity is obviously improved. The low-temperature hydrothermal one-step method is easy to control through hydrothermal media, hydrothermal temperature and hydrothermal time and is a simple and feasible method with application potentiality for preparing high-catalytic-activity BiOI. The method for preparing the ring-shaped BiOI microspheres has the advantages that cost is low, operation temperature is low and equipment is simple.

The invention provides a novel high-efficiency ammonium-excreting combined azotobacter strain which is characterized in that amt B gene is deleted from the whole genome of Pseudomonas stutzeri A1501, and meanwhile, nif A gene is transferred in. The ammonium measurement test proves that the combined azotobacter strain can excrete ammonium at high efficiency and is a potential microbial fertilizer. The invention also provides a method for constructing the high-efficiency ammonium-excreting combined azotobacter strain, which comprises the steps of construction of complete set of expression vectors, triparental mating, screening of recombinants, and identification.

The invention provides a slow-release nano drug carrier as well as a preparation method and application thereof. The slow-release nano drug carrier is nano particles obtained by adsorbing polydopamine to the surface of a nano micelle which is formed by a poly(2-methyl-2-acrylic acid-2-(2-methoxyethoxy) ethyl ester-co-oligo-ethylene glycol methyl ether methacrylate-co-dimethylaminoethyl methacrylate-poly(lactic acid-co-glycolic acid) block copolymer, and the size of the nano particles is 50-1000nm. According to the slow-release nano drug carrier provided by the invention, polydopamine is wrapped on the surface of the micelle by adhesion to form a layer of slow-release film which can improve the slow-release effect of drugs carried in the micelle, so that the slow-release nano drug carrier has a certain application potential.

The invention discloses a preparation method of high(001)-crystal-facet ultrathin anatase nanosheet self-assembled microspheres. The preparation method comprises the following steps: (1) selecting potassium fluotitanate K2TiF6 and dissolving potassium fluotitanate in water to prepare a potassium fluotitanate solution, placing the potassium fluotitanate solution in a hydrothermal reaction vessel, sealing the hydrothermal reaction vessel and adjusting reaction temperature in the hydrothermal reaction vessel to 160-200 DEG C, carrying out a hydrolysis reaction for 1-5 h, and cooling to room temperature after the reaction; and (2) opening the hydrothermal reaction vessel, recovering the residual solution, collecting a sample, and drying to obtain the high(001)-crystal-facet ultrathin anatase nanosheet self-assembled microspheres. According to the preparation method, the synthesis raw materials are simple and easily available, required equipment is common, reaction time is short, reaction temperature is low, the technology is simple, cost is low, size of the synthesized ultrathin anatase nanosheet self-assembled microspheres is uniform, the microsphere surface is composed of (001) crystal facet of ultrathin anatase nanosheet, and the product has high photocatalytic performance and battery electrode application potential.

The invention discloses an Ir-X coating based on surface alloying modification and a preparation method thereof. The preparation method of the Ir-X coating is characterized in that a transition layer,namely a rhenium coating and an iridium coating are deposited on a carbon composite material or a graphite substrate in sequence, and then metal X powder, metallic oxide XO powder corresponding to the metal X and a chloride activating agent are mixed to obtain a permeating agent, and a powder pack cementation method is adopted for enabling the iridium coating to be subjected to surface alloying modification, so as to obtain the Ir-X coating. The Ir-X coating based on surface alloying modification has a low surface catalytic effect and surface temperature in an aerodynamic environment, and isgreatly improved in service performance when compared with the conventional silicide coating system.

The present invention discloses a silicon gate graphene / black phosphorus transistor and a preparation method, and relates to a semiconductor device technology. The transistor disclosed by the present invention comprises a substrate, a gate electrode, a gate dielectric, a source electrode and a drain electrode, and is characterized in that: a silicon oxide isolation layer is arranged on the substrate, a silicon oxide groove is disposed on the silicon oxide isolation layer, the gate electrode and the gate dielectric are disposed inside the silicon oxide groove, a graphene / black phosphorus layer is disposed on the surface of the substrate, and the source electrode and the drain electrode are disposed above the graphene / black phosphorus layer. The silicon gate graphene / black phosphorus transistor and the preparation method have the advantages that: 1, the method is easy to control, is good in process repeatability, and is compatible with a conventional semiconductor silicon process; 2, high gate dielectric quality is easily obtained; 3, filling of a relatively narrow groove is easy to achieve; 4, application potential of large scale integration is realized; and 5, performance of a graphene / black phosphorus film is ensured to the maximum extent.

The invention discloses a transparent electrode and a preparation method thereof. A transparent metal mesh electrode replaces the traditional annealing ITO (Indium Tin Oxide) transparent electrode layer to form ohmic contact in a positive LED (Light Emitting Diode) structure. According to the transparent electrode and the preparation method, a periodic structure is laid as a mask laying metal electrode by a self-assembly method, a transparent function of the electrode is achieved by holes of metal meshes, and the light transmissivity of the electrode can be controlled by controlling an area ratio of holes of a metal film.

The invention discloses a polyarylether with the main chain containing a bisbenzofiurene and triaryl-s-triazine structure and a preparation method of the polyarylether and belongs to the field of the synthesis of polymer materials. The structure of the polyarylether contains a bisbenzofiurene group and a triaryl-s-triazine group and has a structural formula shown in the formula I. The preparation method includes the steps that a bisbenzofiurene-containing bisphenol monomer, a triaryl-s-triazine-containing bishalogen monomer, a bisbenzofiurene-free bisphenol monomer and a triaryl-s-triazine-free bishalogen monomer as raw materials are subjected to a nucleophilic substitution in the presence of a base catalyst, a solvent and a dehydrating agent to obtain the polyarylether. The polyarylether has better solubility in common organic solvents, at the same time, has a higher glass transition temperature (more than 290 DEG C) and a higher thermal decomposition temperature (the 5% weight loss temperature is more than 500 DEG C), is suitable for use as a high performance structural material, and also can serve as composite matrix resin or a functional membrane material and the like.

A mucor podophyllus GJ-TW8 (CCTCC No. M205032) used to prepare podophyllotoxin, its glucoside and kaemplerol flavone is prepared from the root of sinopodophyllum through separation, screening and purifying. It has multiple medicine values.

The invention relates to an aminoacyl-tRNA synthetase mutant. The amino acid sequence of the aminoacyl-tRNA synthetase mutant is selected from a group consisting of an amino acid sequence shown as SEQ ID NO: 4 and conservative variants of the amino acid sequence shown as SEQ ID NO: 4, wherein the conservative variants have the same enzymatic activity as the amino acid sequence shown as SEQ ID NO: 4. The invention provides a 3-methylthio tyrosine translation system. The 3-methylthio tyrosine translation system comprises (i) 3-methylthio tyrosine; (ii) the orthogonal aminoacyl-tRNA synthetase; (iii) an orthogonal tRNA, wherein the orthogonal aminoacyl-tRNA synthetase has a priority of aminoacylating the orthogonal tRNA by using the 3-methylthio tyrosine; (iv) a nucleic acid encoding a target protein, wherein the nucleic acid comprises at least one selecting codon specifically recognized by the orthogonal tRNA.

The invention relates to non-sulfonation high temperature resisting and filtrate loss reduction type water-based drilling fluid. A formula of the drilling fluid provided by the invention comprises the following components based on 100 percent of the weight: 1 percent to 4 percent of bentonite, 0.25 percent to 3 percent of CCM (compound liquid of xanthan gum and N,N'-methylene-bisacrylamide), 2 percent to 4 percent to NMPS (carboxy styrene-butadiene latex), 0.5 percent to 2 percent of MMC (cation emulsified asphalt), 3 percent to 5 percent of Na2CO3, 0.25 percent to 1 percent of DM (high temperature resisting and filtrate loss reduction dispersion liquid) and the balance of water. The drilling fluid provided by the invention has high temperature resisting and filtrate loss reduction performance; a researched synthetic material of the high temperature resisting and filtrate loss reduction type water-based drilling fluid is easy to obtain and low in construction cost, so that the synthetic material is suitable for large-scale industrial production and has oilfield application potential. Furthermore, a drilling fluid system responds to the call on environment protection of China, and the whole system abandons a polysulfonate treatment agent.

The invention relates to a porous structure control method for preparing a functional oxide SiO2 / TiO2 composite film on a substrate through a low-temperature sol-gel method, and belongs to the field of nanometer function material preparation. Ethyl orhosilicate is adopted as a raw material for preparing SiO2 sol, butyl titanate is adopted as a raw material for preparing TiO2 sol, the two kinds of sol are mixed according to a certain ratio, and the prepared SiO2 / TiO2 composite film has abundant regular branch-shaped structures, and by controlling the cross linking reaction among a high-molecular polymer, the SiO2 sol and the TiO2 sol, the porous structure is effectively controlled. The coating is unique in structural design, and the porous structure distributed regularly in a branch shape is shown; the porous structure facilitates water conveying and storage water characteristics, the super-hydrophilic effect and the durability are good, and the self-cleaning function film material is excellent in performance.

The invention provides application of a microbe strain-Enterobacter aerogenes capable of degrading various pyrethroid pesticides simultaneously to the degrading of pyrethroid pesticide residue, and a preparation for degrading the pyrethroid pesticide residue prepared by the strain. An efficient degrading strain is obtained through screening to simultaneously degrade three pyrethroid pesticide residues, namely bifenthrin, fenpropathrin and cypermethrin, and is analyzed and researched in degrading characteristic, so as to disclose the basic rule of the strain for degrading the pesticide and provide scientific basis for controlling pyrethroid pesticide residue.

The invention discloses a bismuth / barium titanate heterojunction for enhancing sonodynamic tumor resistance and a preparation method thereof. The method comprises the following steps of (1), preparing barium titanate nanoparticles by a hydrothermal method; (2), performing high-temperature and high-pressure polarization treatment on the barium titanate nanoparticles; and (3), depositing bismuth elementary substances on the surfaces of the barium titanate nanoparticles by using a one-step in-situ deposition method to construct the bismuth / barium titanate P-N heterojunction. The bismuth / barium titanate heterojunction has good biocompatibility, high safety and good stability, and the sonodynamic tumor resistance effect can be enhanced.

The invention discloses a differential torque power-assisted steering system used for a vehicle driving axle and a control method of the differential torque power-assisted steering system. A detection mechanism collects steering wheel rotating angle information, steering wheel rotating torque information, wheel speed information, battery voltage information and battery current information, and transmits the information to an electronic control unit; a working mode selection unit allows a driver to select different working modes of the differential torque power-assisted steering system, and transmits the working mode information to the electronic control unit; the electronic control unit controls switching of the working modes and controls an electromagnetic clutch, auxiliary motors and brakes of an execution mechanism to work according to the received information; and the auxiliary motors connected with left and right semi-shafts of the drive axle and the brakes arranged on driving wheels on the left and right sides are utilized, the driving wheels on the left and right sides have different driving torque or braking torque, and the vehicle produces an yaw moment to assist the driver to turn, so that force applied on a steering wheel by the driver is reduced, differential torque power-assisted steering is achieved, and the good steering handing feeling is provided for the driver.

The invention relates to an uncooled far infrared thermal imaging system, belonging to the technical field of infrared thermal imaging. The uncooled far infrared thermal imaging system comprises a chopper, a far infrared light lens, a light splitter, an infrared focal plane array, a near infrared light source, a near infrared light lens, a near infrared light filter, another near infrared light lens and a digital camera; and the core component is the infrared focal plane array, the array structure of the infrared focal plane array is a thin film filter in an F-P cavity structure and the material of the cavity is alpha polycrystalline silicon, and the two sides of the cavity are provided with multiple film layers which are alternately formed by alpha polycrystalline silicon thin films and Si3N4 thin films to form a mirror surface structure. In the invention, on the basis of thermo-optic effect principle of the F-P cavity thin film filter, a measuring method of integrated optics is adopted and converting, demodulating and imaging on the optical wave are carried out, so that an interior reading circuit is eliminated and Johnson noise is avoided; meanwhile, vanadium oxide or pyroelectricity material which is usually not matched with silicon can be avoided from being used, devices are highly integrated without influence on the performance thereof, volume is reduced, producing stepsand vacuum packaging cost are reduced, and cost can be greatly reduced; therefore, the uncooled far infrared thermal imaging system provided by the invention has certain application potential.

The invention discloses a preparation method and an application of a brassica napus BnPABP5-3 promoter (PBnPABP5-3). A genome walking method is utilized to clone a PBnPABP5-3 sequence: an SDS (sodium dodecyl sulphate) cracking process is applied to extract genome DNA; in different systems, endonucleases DraI, EcoRV, PvuII and StuI are used to digest DNA, and the digested DNA is respectively connected with joint segments, then primary PCR (Polymerase Chain Reaction) amplification is carried out by taking the DNA connected with the joint segments as templates, and secondary PCR amplification is carried out by taking 50-time diluted solution of products of the primary PCR as a template, thus the PBnPABP5-3 is obtained. The PBnPABP5-3 can be applied to the anther, pollen grain, root tip and ovule of a plant. The promoter has the function of driving expression of a foreign gene, the expression part is in the anther, pollen grain, root tip and ovule of the plant, and the promoter has application potential in the improvement of the safety of rape edible oil, the improvement of the stress resistance and lodging resistance, improvement of the quality of crops, artificial sterile line creation, germ plasma resource enrichment and the like.

The invention discloses a phthalic dicarboxaldehyde-NH3-Na2SO3 reaction-based flow injection spectrophotometry method for measuring Ammonia-N in a water sample. The method specifically comprises the step of adopting a flow injection analyzer and an ultraviolet-visible spectrophotometer to jointly measure Ammonia-N content in a water sample. An amaranth complex is generated based on an OPA(O phthalic aldehyde)-NH3-Na2SO3 reaction; the complex realizes strong absorption at a 550nm position, and has an absorbance value in direct proportion to Ammonia-N concentration in the water sample, thus creating the flow injection spectrophotometry method for measuring Ammonia-N in the water sample. The detection limit of the method can be as low as 0.007mmol / L, and measuring on Ammonia-N concentrations in various surface water can be realized; average substrate adding standard recovery rates of lake water, river water and groundwater are respectively 100.4 percent, 95.2 percent and 101.7 percent; besides, the analysis speed is high, and a result is not remarkably different from that of a indophenol blue spectrophotometry method.

The invention discloses a rape BnPABP 5 gene and the application of a promoter thereof. The sequence of a segregation gene is nucleotide sequence indicated by SEQ ID No. 1, SEQ ID No.2. The promoter comprises a recombinant vector. The invention also discloses the application of the rape BnPABP 5 gene the promoter thereof in controlling pollen fertility and anther. The gene and the promoter thereof are predominantly expressed in the rape anther. The invention further relates to the isolation, cloning, analysis of expression and application of gene BnPABP5 and the promoter thereof for controlling microspore development and the anther fertility. The BnPABP 5 gene has the function of controlling the anther development of rape as well as the pollen fertility. The expression of the BnPABP 5 gene can be weakened through the technique of gene engineering so that the pollen fertility can be controlled and male sterile line materials as well as restorer line materials can be created, therefore, the rape BnPABP 5 gene can be applied to the development and research and the quality improvement of rape andro gamete. The promoter of the BnPABP 5 gene is only predominantly expressed in the anther, and the promoter with tissue preference has higher potential of edible safety on transgenic oil crops, thus having certain development and application value.

The invention discloses a high-thermal stability two-component organic gel. The high-thermal stability two-component organic gel is a mixed system which is prepared from N<1>,N<3>,N<5>-tris(2-ethylhexyl)phenyl-1,3,5-triformamide serving as a first gel factor, triethylamine hydrochloride serving as a second gel factor and a low-polarity organic solvent. According to the two-component organic gel disclosed by the invention, a porous three-dimensional reticular super-molecular structure is constructed through a synergistic effect between the first gel factor and the second gel factor; the formedorganic gel has high thermal stability, namely, gel-solution phase transition.

The invention discloses an unsaturated polyether, a light-cured resin and a preparation method of the unsaturated polyether. The preparation method of the unsaturated polyether comprises the steps of adding diol or polyol, used as an initiator, into a reaction container, adding an active metal cationic catalyst, vacuum dehydrating, introducing an inert gas, and adding a chain extender into the reaction container, wherein the chain extender is glycidyl ether containing unsaturated bonds, glycidyl ester containing unsaturated bonds, glycidyl ether with optical activity or glycidyl ester with optical activity; and controlling a temperature of a reaction system at 0-140 DEG C, and performing ring-opening polymerization for 0.5-3 hours at a stirring speed of 300-500rpm, so as to prepare the unsaturated polyether. The unsaturated polyether prepared by the method can effectively shorten the curing time of the prepared UV-cured resin, improves the cross-linking density of the light-cured resin, and improves the performance of the light-cured resin.

The invention provides a polymer drug carrier and a method for preparing the same. The polymer drug carrier is provided with a core-shell structure, a core comprises polyethylene glycol-distearoyl phosphoethanolamine nano-micelle, and a shell comprises poly-dopamine. The method includes forming the nano-micelle from polyethylene glycol-distearoyl phosphoethanolamine; forming the poly-dopamine shell on the outside of the nano-micelle to obtain the polymer drug carrier. The polymer drug carrier and the method have the advantages that the core and the shell of the polymer drug carrier comprise biodegradable polymers, accordingly, the polymer drug carrier is good in biocompatibility, and few toxic and side effects can be realized; the particle size of the polymer drug carrier is smaller than 50nm, tumor gathering effects and photo-thermal therapy effects can be realized, and tumor cell killing effects can be realized after near-infrared light irradiates on the polymer drug carrier; drugs can be encapsulated by the nano-micelle of the polymer drug carrier, diversified drugs can be loaded under chemical modification effects of the poly-dopamine, and accordingly the polymer drug carrier has an excellent application prospect in the field of medicine and pharmacology.

The invention discloses a coumarin-base Fe < 3 + > fluorescent probe which has a structural formula shown in the specification, and is prepared from multiple raw materials such as p-bromoaniline and paraformaldehyde through a multi-step reaction. The synthesis process has the advantages of mild reaction conditions, short reaction time and high yield. The coumarin-base Fe < 3 + > fluorescent probesolution emits green fluorescence and red fluorescence in a solid state, the fluorescence brightness is high, and all compounds have specific recognition capability on Fe < 3 + >, and are low in detection limit, quick in response and good in stability. Tests show that part of the product has a good inhibition effect on cancer cells.

The invention discloses vibrio natriegens and application thereof and belongs to the field of microorganisms. The provided vibrio natriegens SK42.001 grows rapidly, carries natural plasmids, can express exogenous genes, and has the development value and the application potential to serve as a novel model organism. Meanwhile, the strain contains a gene capable of encoding algin lyase and a gene capable of encoding oligo-algin lyase and can also be used for producing and preparing related products of algin oligosaccharides.

The invention provides cyperaceae crop weeding suspoemulsion as well as a preparation method, application and an application method thereof, which relate to the technical field of agriculture. The cyperaceae crop weeding suspoemulsion provided by the invention comprises prometryn, s-metolachlor and flumioxazin, the action mechanisms of prometryn, s-metolachlor and flumioxazin on weeds are different, prometryn, s-metolachlor and flumioxazin can be mutually matched and promoted after being mixed according to a specific proportion, and the hindering effect on weed growth is enhanced. Thesuspoemulsion not only has a relatively high control effect onannual weeds unearthed, but also has a relatively high control effect on part of weeds which are unearthed during pesticide application, and is high in safety to cyperus esculentus. The preparation method of the cyperaceae crop weeding suspoemulsion is simple and convenient, and the prepared cyperaceae crop weeding suspoemulsion is good in stability and can be used for weed control of cyperaceae economic and medicinal crop fields.

The invention relates to a class of naphthoquinone pyranoindole derivatives, which have a structural general formula represented by the following formula 5, and is prepared by carrying out heating refluxing on substituted 4-hydroxycoumarin, isonitrile and o-bromobenzaldehyde in anhydrous toluene in the presence of K2CO3 under the catalysis of proline-CuI in argon gas. According to the invention, the naphthoquinone pyranoindole derivative has a fluorescence emission peak at 620-650nm and a Stokes shift of 115-125nm, emits red light, has solid-state fluorescence and aggregation-state induced fluorescence effects, can perform fluorescence imagingon human lung cancer (A549) cells, has inhibition effect on multiple triple-negative breast cancer (MDA-MB-231), breast cancer (MCF-7) or human lungcancer (A549) cell strains, and has application potential in the fields of preparation of anti-lung cancer and anti-breast cancer specific drugs and novel red fluorescence imaging probes.

The invention discloses a preparation method of gradient macroporous conductive composite hydrogel applied to a flexible strain sensor, and belongs to the field of flexible electronic materials. Graphene and polyaniline are jointly used as conductive substances, polyacrylamide is used as a flexible substrate, and graphene oxide / polyacrylamide-based composite hydrogel containing a foaming agent is prepared, graphene / polyacrylamide-based conductive composite hydrogel with a gradient macroporous structure is prepared, and aniline in-situ polymerization is carried out, so that the graphene / polyacrylamide-based conductive hydrogel is prepared. The gradient macroporous conductive composite hydrogel is obtained. The gradient macroporous conductive composite hydrogel prepared by the invention has excellent mechanical property and sensing property, high sensitivity, wide strain detection range and good cycling stability, can be widely applied to wearable electronic equipment such as flexible sensors and the like, and has wide application prospects in the fields of human motion monitoring and the like.

The invention relates to a method for measuring perfluorooctane sulfonate by using dual-wavelength ratio ultraviolet spectroscopy, and belongs to the field of physical and chemical inspection research. Perfluorooctane sulfonate molecules do not have ultraviolet absorption functional groups and do not have ultraviolet absorption properties. In the method provided by the invention, the ultraviolet absorption generates electrostatic interaction with toluidine blue under acidic conditions to form an ionic associate, the ionic associate shows two characteristic peaks at 632 nm and 502 nm and performs rational absorption, the concentration of a perfluorooctane sulfonate solution has a good linear relationship with an ultraviolet dual-wavelength absorption ratio value under selected conditions, and the dual-wavelength ratio ultraviolet spectroscopy for measuring the perfluorooctane sulfonate is established accordingly. The method provided by the invention is suitable for measuring the perfluorooctane sulfonate in environmental water samples, and has the advantages of simple and convenient operation, high sensitivity, strong anti-interference ability and the like.