51results about How to "Increase response current" patented technology

This invention discloses one static fabric processed fixed enzyme electrode and its method, which belongs to fixed enzyme electrode technique, wherein, the said enzyme electrode is composed of electrode base, reacting layer composed of polymer nanometer fiber film and oxidation and deoxidizing enzyme or the reacting layer is composed of polymer nanometer fiber film and oxidation and deoxidizing enzyme and metal particles with 5 to 100 nanometer electric activity or the reacting layer is composed of polymer nanometer fiber film and film oxidation and deoxidizing enzyme and electro medium.

A method adopted by an electrochemical biosensor based on sulfonic functionalized grapheme-chitosan to detect methyl parathion belongs to the technical field of electrochemical sensors and is used for detecting methyl parathion residual quantity in vegetables, fruits and products thereof. The basis of the invention is that methyl parathion can play an inhibition role on acetylcholinesterase, and the acetylcholinesterase can catalyze acetylthiocholine chloride to achieve electrochemical reaction of hydrosulfuryl acetylcholine. Sulfonic functionalized grapheme-chitosan is decorated on the surface of a bare glass carbon electrode, so that not only acetylcholinesterase is effectively fixed on the electrode, but also an electrochemical signal is amplified; and the methyl parathion residual quantity is related with electrochemical summit current, so that a standard curve for quantified detection of methyl parathion is built. The invention aims to provide the methyl parathion quantified detection method with high sensitivity and strong operability and develops the application of novel material graphene.

The invention provides a preparation method of an electrochemical sensor for detecting heavy metal ions. The preparation method includes the following steps: 1) performing carboxyl functionalization to multi-wall carbon nano-tubes and performing in-situ synthesis with zirconium chloride and 2-aminoterephthalatic acid to prepare an MWCNTs@UiO-66-NH2 composite material; 2) dispersing the MWCNTs@UiO-66-NH2 composite material in N,N-dimethylformamide to prepare a suspension liquid, drop-coating a surface of a glass carbon electrode with the suspension liquid until the surface of the glass carbon electrode is completely covered thereby, and drying the glass carbon electrode in a drying device at room temperature to prepare the MWCNTs@UiO-66-NH2 composite material electrochemical sensor. The electrochemical sensor can achieve ultrasensitive detection on a sample. By an analysis method in the invention, an accurate analytic result can be acquired.

The invention discloses a preparation method of an aptamer sensor for detecting antibiotic residue, belonging to the technical field of safety test of agricultural products. The method comprises the steps of carrying out electrochemical polymerization on a gold electrode and thionine to obtain electrically polymerized thionine electrode; after that, evenly dripping the prepared carbon nano tube-graphene nano-composition onto the surface of the electrically polymerized thionine electrode; drying in the air, and then soaking the electrode into antibiotic aptamer solution; washing, drying in the air, and closing by bull serum albumin (BSA) solution to obtain the antibiotic aptamer sensor. The prepared aptamer sensor has the advantages of not needing pretreatment, being high in analysis speed, simple in an operation system, high in accuracy, high in specificity, low in cost, rapid in response and the like, and has the limit of detection reaching up to 0.8nm, thus being suitable for rapidly detecting the antibiotic residue.

The invention discloses a method for manufacturing an immunosensor for detecting chlorpyrifos, which belongs to the technical field of biologic sensor manufacturing. The method comprises the following steps: dropwise coating the surface of a naked glassy carbon electrode, which is subjected to cleaning, activation and performance testing, with a nickel aluminum hydrotalcite-graphene compound liquid, subsequently modifying by hollow nanogold, further fixing a chlorpyrifos monoclonal antibody on the modified electrode, and finally, sealing by bovine serum albumin. The immunosensor manufactured by the method has the characteristics of high sensitivity, low cost, high detection speed, good stability and high sample recycling rate. The detection limit of the immunosensor manufactured by the method can be 0.052ng/L, the linear range of the immunosensor is 5ng/mL-2 micrograms/mL, the recycling rate of the immunosensor can be 82.0-118.0%, and therefore the immunosensor is applicable to rapid detection on the residual amount of chlorpyrifos in fruits and vegetables.

The invention provides a micron-sized diode chip. The micron-sized diode chip comprises a first table surface, a second table surface, a gallium nitride layer, an n-GaN layer, a stress release layer,a multi-quantum-well light-emitting layer, a p-GaN layer, a first electrode, a second electrode and an insulating layer, wherein the sizes of the first table surface and the second table surface are different. The technical problems that an original LED is low in output light power and large in mismatch with GaN in thermal expansion rate and lattice constant are avoided; and the technical effectsof integration of multiple functions of communication, illumination, detection and the like on the same chip, and high light extraction efficiency are achieved.

The invention discloses a preparation method of an aptamer sensor for pesticide detection, and belongs to the technical field of safety detection of agricultural products. The preparation method provided by the invention comprises the following steps: drop-coating carbon black-chitosan compound liquid on a surface of a bare glassy carbon electrode after cleaning, activation and performance testing; then, modifying with a graphene oxide-iron oxide compound; immobilizing a pesticide aptamer on the modified electrode; and finally, closing with bovine serum albumin. The aptamer sensor prepared in the invention has characteristics of high sensitivity, low cost, high detection speed, good stability and high sample recovery rate, has a detection limit of 0.033 ng/mL, a linear range of 0.1-105 ng/mL, a recovery rate of 96.0-106.0%, and is suitable for rapid detection of pesticide residues in fruits and vegetables.

The invention provides a method for preparing a metal micro-nano array electrode by using a ZnO crystal as a template. The method employs a ZnO crystal array as the template and comprises the steps of submerging the template by photoresist, dissolving ZnO away after the photoresist is stabilized, and electrodepositing the metal crystal in holes formed by dissolving ZnO away. The obtained metal crystal has ZnO morphology, being in hexagonal prism shapes.

The invention relates to a method for detecting phenol compounds by using an aluminum oxide nanoparticle/chitosan/horseradish peroxidase composite film-modified glassy carbon electrode and belongs to the technical field of electrochemical analysis detection. The key point of the method is to obtain the modified glassy carbon electrode which is equivalent to a current type biosensor by dispensing a certain amount of aluminum oxide nanoparticle/chitosan/horseradish peroxidase mixed solution on the surface of the glassy carbon electrode and use the aluminum oxide nanoparticle/chitosan/horseradish peroxidase composite film-modified glassy carbon electrode to quantitatively detect the phenol compounds. The method has the characteristics of quickness, sensitivity, accuracy, stability and the like.

The invention relates to an on-line monitoring method for the end insulation state of an inverter driving motor, and the method comprises the steps: 1) collecting current signals on three-phase phase lines of the motor, and intercepting a switch high-frequency oscillation current segment; 2) decomposing the intercepted switch high-frequency oscillation current segment into three sub-modes by using a variational mode decomposition algorithm, obtaining a high-frequency common-mode current and a center frequency thereof, and taking the center frequency of the high-frequency common-mode current as an extracted frequency feature; 3) calculating the total variation of the three-phase insulation capacitance by using the center frequency of the high-frequency common-mode current; and 4) obtaining the amplitude variation of the three-phase high-frequency common-mode current at the resonance point as an extracted amplitude feature, and carrying out fault phase positioning by using the amplitude feature. Compared with the prior art, the method has the advantages of high sensitivity, high robustness, high safety and the like.

The invention discloses an artificial nerve synaptic device and a preparation method thereof. The artificial nerve synaptic device comprises a first electrode layer, a second electrode layer and a function layer arranged between the first electrode layer and the second electrode layer. The resistive random access device prepared based on the material of the function layer has a unidirectional resistive random access characteristic and a bidirectional resistive random access characteristic at the same time. According to the artificial neural synaptic device and the preparation method thereof, related characteristics of associative learning and non-associative learning can be realized at the same time, and when the related characteristics of non-associative learning are realized, a three-terminal transistor does not need to be matched, and complex excitation conditions do not need to be provided.

The invention relates to a graphene photoelectric detector based on an interdigital electrode structure. The photoelectric detector comprises a substrate layer and an optical waveguide disposed on thesubstrate layer. The optical waveguide is provided with a dielectric isolation layer; the dielectric isolation layer is provided with two metal layers which are not in contact with each other; the two metal layers serve as electrodes; graphene layers are arranged on the two metal layers; and the graphene layers serve as light absorption layers. The provided graphene photoelectric detector based on the interdigital electrode is compatible with a CMOS process and has high performance.

The invention discloses a novel memory material - an amorphous solid electrolyte membrane (AgI) x (AgPO3)1-x, which is utilized to prepare a nonvolatile memorizer and can be used for an integrated circuit like information storage and other varieties. The amorphous solid electrolyte membrane (AgI) x (AgPO3)1-x of the invention is characterized in that: the (AgI) x (AgPO3)1-x is a solid electrolyte membrane material, has ionic conductivity, can be reversibly converted into electronic conductivity under certain conditions and takes the structure of an amorphous material under room temperature, and the nonvolatile memorizer with small size, high density and stable performance can be prepared by utilization of the membrane. The invention provides a preparation method for the amorphous solid electrolyte membrane (AgI) x (AgPO3)1-x, comprising the following steps: AgI, AgNO3 and (NH4)2HPO4 with adequate mixture ratio are melted and then fabricated into glass target materials, and then the amorphous solid electrolyte membrane is prepared by utilization of a laser pulse sedimentation method.

The invention provides a preparation method of an ionic liquid electrolyte system for an electrochemical oxygen sensor. The preparation method comprises: mixing alkyl imidazole, alkyl halide and hexafluorophosphate in a ratio of 1:1.1:1.1, heating and refluxing in a water bath at 60-90 DEG C for 3-5 h, cooling, and washing with water until it is detected that no precipitate is produced in the upper layer of silver nitrate solution to obtain AMIMPF6 (1-alkyl-3-methylimidazolium hexa uorophosphate); mixing the AMIMPF6 with allyl imidazole, and ultrasonically treating for 1-2 h until uniform mixing; preparing electrolyte solution of electrodeposition inorganic matters, applying cathode current constantly in -5 mA to electrically deposit for 2400-360 s, collecting an inorganic catalyst by ultrasonic vibration, and mixing in the inorganic catalyst to obtain the final electrolyte. The preparation method is capable of synthesizing electrochemical oxygen sensor electrolyte high in oxygen sensitivity, good in catalytic performance and easy to prepare.

A multi-wall carbon nanotube/poly L-histidine compound membrane electrode (MWCNTs/poly-L-HiS/GCE) is prepared by polymerizing L-histidine to a glass carbon electrode and then dropping a multi-walled carbon nanotube suspension liquid to poly-L-HiS/CGE. In a PBS buffer solution, the pH of which is 7.0, an electrochemical behavior of hydroquinone (HQ) on a modified electrode is researched by virtue of cyclic voltammetry, and the property thereof is represented by means of electrochemical impedance spectroscopy (EIS), influence on hydroquinone determination by sweep rate, pH and etc. are discussed, the experimental condition is optimized, and finally, the HQ solutions with different concentrations are determined by means of differential pulse voltammetry (DPV). Experimental results verify that the response current on a composite electrode of HQ is obviously enhanced, and a good linear relationship with an oxidation peak current (Ipa) in a concentration range of 5.0*10<-8>-8*10<-4>mol/L is shown. The coefficient of association is 0.998, and when the signal to noise ratio is 3, the detection limit is 1.0*10<-8>mol/L.

The invention relates to a preparation method of an electrochemical sensor used for sensitively detecting copper ions. The preparation method includes the following steps: synthesizing polyvinylpyrrolidone (PVP)/cobalt oxyhydroxide composite material through a hydrothermal method; and carrying out drip-coating of polyvinylpyrrolidone/cobalt oxyhydroxide suspended liquid on a glassy carbon electrode, and carrying out drying under an infrared lamp to obtain the electrochemical sensor by preparation. Cobalt oxyhydroxide has good electrochemical catalytic activity, complexation of heteroatoms (nitrogen and oxygen atoms) in polyvinylpyrrolidone and the copper ions shows high selectivity, combination of the two parts enables the electrochemical sensor of the invention to have high specific response to the copper ions, and sensitive detection on a trace amount of copper ions is realized. According to the electrochemical sensor to which the invention relates, preparation is simple, costs are low, stability is good, a linear range is wide, sensitivity and selectivity are high, and a fast, effective and sensitive method with high accuracy is provided for detection of copper in soil, water and food.

The invention discloses an attapulgite/nitrogen-doped graphene modified glassy carbon electrode, a preparation method of the glassy carbon electrode, and application of the glassy carbon electrode, insynchronous detection of catechol and hydroquinone. The method comprises the following steps: mixing acid-modified attapulgite and nitrogen-doped graphene according to a mass ratio of (2-4):1, and ultrasonically dispersing in N,N-dimethylformamide; dispensing the dispersion on a glassy carbon electrode, and preparing a Pal/NGE modified glassy carbon electrode constructed by the composite film andglassy carbon electrode. The attapulgite/nitrogen-doped graphene modified glassy carbon electrode disclosed by the invention is simple in preparation, green, economic and low in cost. The attapulgite/nitrogen-doped graphene modified glassy carbon electrode can be applied to synchronous detection of catechol and hydroquinone and is excellent in reproducibility, high in stability and short in response time, and the lowest detection limit of the catechol and hydroquinone is respectively 0.13umol/L and 0.8 umol/L.

The invention relates to an electrochemical method for measuring COD of surface water. The electrochemical method comprises the following steps: (1) measuring background currents I1 and I2 of a background test solution consisting of deionized water and sodium sulfate under constant voltages V1 and V2; (2) measuring a response current I3 of a surface water test solution composed of surface water, deionized water and sodium sulfate under the constant voltage V1, respectively adding an organic matter capable of increasing the COD of the solution by X1 or chloride capable of increasing the chloride ion concentration of the solution by Y1, and measuring response currents I4 and I5 under the constant voltage V1; (3) according to the method in the step (2), respectively measuring the response current I6 of the surface water test solution, the response current I7 of the COD increased by X2 and the response current I8 of the chloride ion increased by Y2 under the constant voltage V2; and (4) calculating the COD value in the surface water according to a formula. The invention provides the method for measuring the response current of the surface water test solution under different conditionsby using the electrochemical device and calculating the COD value of surface water.