37results about How to "Improve sensing characteristics" patented technology

A pressure detection device includes a sensing part that outputs an electrical signal responsive to an applied pressure, a pressure receiving diaphragm that receives a pressure from a subject device, a cylindrical stem having a first end connected to the sensing part and a second end connected to the pressure receiving diaphragm, and a pressure transmission member located within the cylindrical member to transmit the pressure received by the pressure receiving diaphragm to the sensing part. In the pressure detection device, a side wall portion of the cylindrical stem has a spring portion which is provided to generate an elastic force in an axial direction of the cylindrical member. Accordingly, fluctuations in a spring characteristic acting on a pressure transmission mechanism of the pressure detection device can be effectively restricted by the spring portion.

The invention relates to a cascade long-period pohotonic crystal fiber grating temperature sensor. A photonic crystal fiber is provided with a cladding consisting of periodically arrayed air holes; the cladding and a fiber core of the fiber are made of SiO2; a long-period grating with a certain period is written onto the fiber; the air holes of the cladding are filled with thermosensitive substances sensitive to temperature; the refractive indexes of the thermosensitive substances are less than the refractive index of the fiber core; and the total internal reflection photonic crystal fiber is formed. The effective refractive index of a coupled mode of the grating can be changed by controlling the temperatures of the thermosensitive substances, so that the resonant wavelength of a transmission spectrum of the grating is changed, the temperature variation is shown as spectral shift, and the wavelength-tunable temperature sensor is realized. As the bandwidth of the transmission spectrum of the single long-period grating is greater, the temperature sensitivity and the measurement precision of the transmission spectrum of the long-period grating are limited, and the sensor is transformed into a cascade long-period grating structure. The sensor achieves the tunable wavelength, the sensitivity is improved, and the sensor has a very large application prospect in the transduction field.

The invention relates to a fiber sensor, particularly relates to a multifunctional sensor with microstructure fiber surface plasma resonance and a preparation method thereof. The two sides of the photonic crystal fiber substrate of the fiber are provided with fan-shaped openings that surface of which are plated with gold films. Tips of the bottom ends of the fan-shaped openings are provided with silver nanowires. The core of the photonic crystal fiber substrate is provided with a magnetic fluid, and the outer side of the core is provided with a cladding air hole. The preparation method comprises the steps of: polishing the fan-shaped openings on the photonic crystal fiber; filling the silver nanowires; uniformly plating the gold films on the surface of the fan-shaped openings; pressing themagnetic fluid into the photonic crystal fiber from a small tube; and coupling and splicing the two ends of the common single mode fiber and the photonic crystal fiber through the self-calibrating function of the a fiber fusion splicer. The sensor of the invention can achieve the analysis and detection of the external magnetic field intensity, the refractive index of the to-be-measured liquid andthe external temperature in one time, therefore, the technical defects that the conventional detection technology is complex in operation, low in detection sensitivity and non-real time online detection are overcome.

The invention discloses an ultrathin film and a preparation method of an organic field-effect transistor sensor based on the ultrathin film. The preparation method is characterized by comprising the following steps: blending a polymer semiconductor material and a polymer insulating material in an organic solvent, and performing spin-coating to form a double-layer film; dissolving to remove the polymer insulating material film by adopting a good solvent, and obtaining the ultrathin film of the polymer semiconductor material; evaporating an electrode on the film, thereby obtaining the organic field-effect transistor sensor. The ultrathin film disclosed by the invention has the advantages of simple operation, high repeatability, low requirements on equipment and process conditions, no need of large precise instruments and equipment and the like; because the active layer has ultrathin thickness, the obtained sensor in the invention has the advantages of high sensitivity, high selectivity, low detection limit and the like, and has an important application prospect in the aspect of improving the sensing property of a gas sensor.

The invention provides a voltage regulatable anisotropic magnetoresistive sensor and a manufacturing method thereof, and belong to the technical field of spinning electron sensors. A magnetoresistivesensor includes a substrate, and a multilayer film and a nonmagnetic heavy metal film formed on [nonmagnetic metal oxide film/magnetic regulation layer/magnetic response layer]n on the substrate in sequence, wherein n>=1. The voltage regulatable anisotropic magnetoresistive sensor has characteristics of simultaneous regulation of magnetic field detection range and magnetoresistance change rate while achieving good sensing characteristics, and can be widely applied to fields of rotational speed control, angle control, magnetic field detection, and magnetic switches and other intelligent controlfields.

The invention provides a refractive index sensing device based on tilted fiber grating surface plasmon resonance. The device consists of a broadband light source, a polarizer, a polarization controller, an optical isolator, a sensing probe formed by excessively tilted long period fiber grating and a metal film, and a spectrum analyzer. The broadband light source produces broadband incident light,after the incident light passes through the polarizer, the polarization controller and the optical isolator, single polarized light is output and is introduced into the parameter optimized sensing probe, the polarized light is coupled to a low order or high order polarization cladding mode in the sensing probe and produces a corresponding resonance peak at the output end. Specifically, the s polarized light is only coupled to an s polarization low order or high order cladding mode, the p polarized light is coupled to a low order or high order p polarization cladding mode and excites plasma resonance wave in the metal film. The spectrum analyzer records the variation situation of the output spectrum's resonant wavelength along with the refractive index of a to-be-tested sample, thus realizing detection of the to-be-tested sample. The sensing device provided by the invention effectively enhances the degree of interaction between the to-be-tested sample and the surface plasma resonance wave, and improves the sensing sensitivity and resolution.

The invention discloses a carbon fiber packaged optical fiber Bragg grating sensor and a manufacturing method thereof. By being packaged in a carbon fiber, the optical fiber Bragg grating has an excellent sensing character and maximum data linearity of 0.99949. The designed sensor has the advantages that the packaging process is simple and the material cost is low. Various individual long-term tests show that the wavelength drifting of the sensor is 0, the repeatability and stability are excellent, and the sensor is fit for large-scale batch production and meets the demand of long-term use.

The invention belongs to the technical field of gas sensor preparation, and discloses an acetone sensor, a preparation method and an acetone detection method. Cobalt nitrate is used as a metal salt, an ethanol/water mixed solution is used as a solvent, ammonium fluoride is used as a surfactant, and an okra-shaped Co3O4 material is successfully prepared through a one-step chemical hydrothermal method; and materials are coated according to a side-heating device process, assembling and welding are carried out to finish the preparation of the okra-shaped Co3O4 sensor. The Co3O4 gas sensitive material is successfully synthesized through a one-step hydrothermal method. The synthesis method is simple and low in cost. According to the invention, a one-step hydrothermal method is adopted, ammonium fluoride is used as a structure-directing agent, the composition of the solvent is changed, the construction of a hierarchical structure is successfully achieved, the synthesis method is simple, and the cost is low. The acetone sensor has excellent gas sensitivity, the sensitivity is 35.2, the optimal working temperature is 150 DEG C, and effective detection of acetone in a low-temperature and high-humidity environment is achieved.

The invention provides a gas sensing device. The sensing device comprises a flexible sensing component and a strain providing component, wherein the flexible sensing component comprises a flexible substrate, a MoS2 sensing layer arranged on the substrate, and electrodes arranged at two ends of the MoS2 sensing layer, the strain providing part 20 is used for providing strain for a flexible sensingpart 10, an illumination providing component can be further included, and illumination conditions are provided for the flexible sensing component. The sensing device shows higher sensitivity in a flexible sensing part activated by illumination and piezoelectric photoelectronic effects, and the response (recovery) time of the sensing device is sharply shortened.

The invention discloses a fiber grating sensor based on settlement measurement of a transformer substation. The fiber grating sensor comprises a first connecting piece (1), an optical fiber Bragg grating (2), a second connecting piece (3), an extension spring (4) and a third connecting piece (5) which are connected in sequence from top to bottom, wherein the first connecting piece (1) is also fixedly connected to a reference point on a reference plane; the third connecting piece (5) is also fixedly connected with precipitates of the transformer substation. Compared with the prior art, an optical fiber settlement sensor can be used for accurately converting settlement displacement into tensile stress acting on the optical fiber Bragg grating, further converting the tensile stress into an optical parameter transmitted in an optical fiber, and obtaining an accurate settlement displacement by solving a transmission optical spectrum, so that the working efficiency of working personnel is increased, and a large amount of settlement data is acquired in real time; the monitoring time is short, the influences of severe environments are avoided, and the accuracy is increased greatly.

An electrochemical sensor and method of detecting gaseous analytes are provided, which involve the use of a working electrode comprising edge plane pyrolytic graphite.

The present invention belongs to the metamaterial sensor technical field and provides a polarization sensor structure for realizing sensor functions in microwave low frequency bands, in particular an artificial surface plasmon-based polarization sensor. The artificial surface plasmon-based polarization sensor is characterized in that: subwavelength periodic trenches are formed in an ultra-thin metal cylindrical structure; the trenches are filled with dielectric materials; the dielectric constants of the materials are uniform; the depths of the trenches in the cylinder are different; the center of a cylindrical portion with no trenches formed inside does not overlap with the center of the structure of the whole cylinder; when electromagnetic waves enter the surface of the structure, a probe at one side of the structure can detect different field intensities for the electromagnetic waves which enter the structure from different directions, so that the function of the sensor can be realized. The sensor has the advantages of simple manufacture, low cost and high economic efficiency.

The invention discloses an arrangement method of a uniform-speed pipe flowmeter for measuring the air supply volume of a variable-air-volume air conditioner terminal unit, which comprises the following steps of: S1, performing computer modeling simulation on the terminal unit to obtain the characteristics of an air flow field in an air duct; selecting an m * n position array in the air duct as a preset position of the flow meter; s2, respectively performing calculating according to the preset height of the flowmeter, and comparing the consistency of the airflow velocity distribution curve andthe theoretical wind speed value on the section of the same height to obtain a corresponding optimal horizontal position; and S3, based on the optimal layout position, taking the intersection point ofthe airflow speed distribution curve and the theoretical air speed value under the preset air volume as a measuring hole of the flow meter, comparing the average relative error between the speed measurement value and the theoretical air speed value under other air volumes, and determining the optimal layout scheme. The whole process information of air flowing through the variable-air-volume air conditioner terminal unit is obtained through the computer simulation technology, accurate measurement of the air supply volume of the terminal unit is achieved, and the regulation and control performance of operation of the variable-air-volume air conditioner system is guaranteed.

The invention discloses a titanium dioxide film coating inclined fiber grating refractive index sensor and a detection system. Inclined fiber grating is coated with a titanium dioxide film to serve asa sensor, polarized light is input to enter a great inclined angle grating area of the sensor and then is coupled to an s polarization state TE0, a j coating film or a p polarization state EH2; the jcoating film, not the traditional HE/EH1, can work in the s polarization state TE0 and j or p polarization state EH2 by further regulating and controlling the polarization coupling characteristic anda resonance parameter of the sensor; the j coating film is in a double-peak resonance state, TE0, j and EH2; the j coating film has specific HE/EH1; the j coating film has sensitive environment response characteristic, so the interaction degree of the sensor and a to-be-detected substance is enhanced and more excellent sensing characteristic is achieved; further, the scheme effectively utilizes afiber mode resource and is favorable for developing optical fiber sensors with multiple parameters, more excellent spectrums and sensing characteristic.