59results about How to "Simple test principle" patented technology

The invention provides a novel adsorption and desorption experiment device and a novel adsorption and desorption experiment method. The device mainly consists of a reference cylinder, a sample cylinder, a confining pressure pump, a booster pump, an air compressor, an intermediate container, a constant temperature system, a pressure sensor and a computer, wherein the sample cylinder mainly consists of a sample chamber, a confining pressure chamber, a left adjustable plug, a right adjustable plug, a barrel, a sealing ring, a screen mesh and a leather sheath; the confining pressure chamber is defined by the barrel and the leather sheath; the sample chamber is defined by the leather sheath and the adjustable plugs; the sample chamber is connected with the reference cylinder; the reference cylinder, the sample cylinder and the pressure sensor are arranged in the constant temperature system; the confining pressure chamber is connected with the confining pressure pump, and the confining pressure pump is used for increasing the confining pressure of the confining pressure chamber, so that the real stratum conditions can be simulated; the sample cylinder is provided with the two adjustable plugs, one adjustable plug is provided with the screen mesh on the top, and the other adjustable plug is not provided with the screen mesh, so that two rock samples including standard rock samples (having length of 5cm and diameter of 2.5cm) or rock sample powder (with 60-80 meshes) can be arranged in the sample cylinder. The device and the method have the advantages that the principle is reliable, and the device is simple in structure and simple and safe to operate; the real stratum environment can be simulated, and temperature and pressure conditions of different reservoir stratums as well as the methane adsorption and desorption law of the rock samples can be determined, so that reasonable experimental data can be provided for shale gas occurrence form research and reserve calculation.

The invention relates to a single tower cable-stayed bridge model test system based on damage identification for the field of bridge test science. The test system comprises a single tower cable-stayed bridge model, a lever loading system and a cable tension test system, wherein the single tower cable-stayed bridge model comprises a main bridge, a main tower, a stayed cable, a support, a base and a support upright which are assembled together; the lever loading system comprises a gantry device, a lever device and a lintel device, wherein the gantry is transversely arranged above the main beam of the single tower cable-stayed bridge model, and the lintel device is placed on the main beam of the single tower cable-stayed bridge model; and the cable tension test system comprises an anchoring screw, a leveling block, a pressure ring sensor and an adjusting nut which are mounted in a cable beam anchoring area. According to the invention, model tests for the dynamic and static performance ofthe cable-stayed bridge and experimental studies on the damage identification method of the cable-stayed bridge structure can be performed; and moreover, real-time and quick measurement of the cable tension can be realized without changing the cable rigidity, and thus the problem of difficult measurement of cable tension in the cable-stayed bridge model is solved.

The invention relates to a device and method for determining a molecular diffusion coefficient of a multi-component gas-liquid system in a rock core. The device mainly comprises an inlet pump, a confining pressure pump, a pressure returning pump, an intermediate container, a rock core clamper, an oil-gas two-phase separator, a pressure sensor and a computer, wherein one end of the intermediate container is connected with the inlet pump; thee other end of the intermediate container is connected with the rock core clamper; the rock core clamper is connected with the pressure return pump, the confining pressure pump and the oil-gas two-phase separator; and two ends of the rock core clamper are connected with the pressure sensor and the computer. The method comprises the following steps of: transferring an oil sample and a gas sample into the rock core through the inlet pump; contacting an oil phase with a gas phase to generate diffusion and cause the reduction of the gas phase pressure; monitoring the pressure change of a gas phase zone; after the gas and liquid reach the balance, enabling the drained fluid in the rock core to enter the oil-gas two-phase separator; and analyzing and testing the gas phase composition and the property change. The device and method disclosed by the invention are reliable in principle and simple and convenient in operation; and the molecular diffusion coefficient of each component of the multi-component gas-liquid system in real rock core in the gas phase and oil phase can be determined under different temperature and pressure conditions of an oil reservoir and reasonable base data is provided for quantitatively evaluating the influence on the improvement on the recovery ratio caused by a molecular diffusion effect.

The invention aims to provide a non-smooth surface fluid friction resistance testing device and a testing method. The testing device comprises a pool, a buoyancy material, a support, a fixed pulley, a weight and a pull rope. A flat plate to be tested and the buoyancy material are fixed together, the pool is filled with fluid, and the flat plate to be tested and the buoyancy material jointly float on the fluid. The support is fixed to the position beside the pool, the fixed pulley is installed on the support, the pull rope is wound around the fixed pulley, one end of the pull rope is connected with the buoyancy material, and the other end of the pull rope is connected with the weight. The pull rope keeps horizontal between the fixed pulley and the buoyancy material and is higher than the wall surfaces of the pool, namely the tension exerted on the buoyancy material is equal to the gravity of the weight, the gravity of the weight is larger than the friction resistance of the flat plate, and thus the flat plate can move forward under the effect of gravity of the weight. The testing principle is simple and visualized, the testing device is different from other devices used for estimating a resistance reduction effect of a non-smooth surface, the friction resistance of the non-smooth surface can be directly tested, and the testing result is reliable.

The invention relates to a testing device of bonding strength of a thermal spraying coating on a metal surface for testing the bonding strength of a coating with high bonding strength (larger than 80MPa). The testing device consists of a centering component and a testing specimen; the centering component comprises an upper part and a lower part, and respectively consists of an upper pull rod, an upper centering sleeve, a lower pull rod and a lower centering sleeve; the matched surfaces of the upper and lower pull rods with the upper and lower centering sleeves are spherical surfaces, and 360-degree centering fine tuning is realized under the effect of drawing force; the testing specimen consists of a loading block, a coating, a support block, a pressing sheet and a base body conical column pin; the center of the support block has a through conical hole with the taper of 15 degrees-30degrees equal to the taper of the base body conical column pin; the base body conical column pin passes through the conical hole of the support block, and the support block at the other side and the end surface of the base body conical column pin are in the same plane; the loading block and the pressing sheet have two round through holes which can be respectively connected with two threaded through holes of the support block by bolts. The testing device and the testing method have the characteristics of simple testing principle, simplicity and flexibility in operation, high result accuracy and the like.

The invention discloses a push-pull force testing device of an actuator. The push-pull force testing device of the actuator is mainly composed of the actuator (1) provided with a push rod and a braking mechanism limiting the movement of the push rod. A push-pull sensor (2) is arranged between the push rod and the braking mechanism, and the braking mechanism is a control assembly provided with a support structure and comprises a brake (3) and a brake pad (4), wherein the brake (3) is fixed on the support structure, and the brake pad is controlled by the brake (3). The brake pad (4) is arranged along the moving direction of the push rod, and two ends of the push-pull force sensor (2) are respectively connected with the push rod and the brake pad (4). The push-pull force testing device is mainly used for a linear stroke actuator, a detecting scheme is provided to aim at the push rod force, a testing principle is simple, a gap of push-pull testing of the actuator in the prior art is filled, and not only is the control precision of the operating position of a valve improved, but also the push-pull force testing device has the advantages of being simple in structure and easy to operate.

The invention relates to a cable open-circuit point position detecting method, including the following steps: 1. selecting two uniform lead wires with equal distances and lengths from the cable, wherein the lead wire cd is an open-circuit lead wire; 2. connecting two test pens of a capacitance testing instrument or equipment with the end point a of the lead wire ab and the end point c of the lead wire cd to measure the distributed capacitance C1 between the lead wire ab and the lead wire cd; 3. connecting two test pens of the capacitance testing instrument or equipment with the end point b of the lead wire ab and the end point d of the lead wire cd to measure the distributed capacitance C2 between the lead wire ab and the lead wire cd; 4, calculating the relative distance X from the open-circuit point position to the end point c according to the formula. The method solves the technical problems that the existing cable fault point detecting method has high test requirement and complex test process, and has the advantages of convenience and easiness in operation.

The invention discloses a method for testing the surface shape of a reflector in a zero gravity state. By means of the characteristic that supporting deformation does not change in a mirror plane rotation test, a solution formula of the supporting deformation is obtained through derivation according to the differential integration principle; a surface shape test sequence is obtained through multiple tests of different directions of mirror plane rotation, and then a conventional data processing method is used for obtaining accurate zero gravity deformation. According to the method, the testing principle and the data processing process are simple, simulation analysis and error calculation are not included, and the test precision is high; the objective testing principle and data processing method are adopted, so that the requirement of space application for reliability is met; the requirement for the supporting deformation is low, and the development cost for a supporting unloading mechanism is low.

The invention relates to a transformer substation starting test wireless nuclear phase debugging method. The method includes the following steps: using a GPS / Big dipper satellite to provide accurate absolute time to a system, supplying a radiofrequency wireless time service module; the radiofrequency wireless time service module using second pulse of the GPS / Big dipper to provide accurate time service pulse to different data acquisition modules; each data acquisition module acquiring a three-phase voltage of a device under nuclear phase, and based on the time service pulse, conducting time stamping on the acquired data, recording generation time of the data, and real-time transmitting the data to a data processing and analyzing terminal through wireless communication; the data processing and analyzing terminal in according with the time when the data is received, processing the data transmitted by the different data acquisition modules, extracting a fundamental component and a phase of the data in different phases, finally displaying data processing results through a display and control platform. According to the invention, the method addresses the problems of large amplitude difference of the device under nuclear phase, containing of harmonic component, and screen cabinet. The method increases accuracy and reliability of work in transformer substation starting nuclear phase debugging.

The invention discloses a rapid determination device of the salt corrosion resistance performance of concrete and a determination method thereof. The device comprises a testing part, a control part, a supporting part and a detected part, wherein the testing part comprises a working box and a water tank; the working box is internally provided with waterproof electric heating wires, a bubble making device, and concentration and temperature testers; the working box is communicated with the water tank and the side wall of the working box is provided with a tool box water outlet; the side wall of the water tank is provided with a water tank water outlet; a water inlet is formed in the upper end of the water tank; a rotary shaft is fixed in an axial direction of the working box; the supporting part comprises a supporting water tank, a water pipe and a rotary shaft; and the control part comprises a motor for driving the rotary shaft to rotate and a control panel for controlling the motor. Aiming at the test of the salt corrosion resistance performance of the concrete, the rapid determination device is used for evaluating the salt corrosion resistance performance of the concrete and has the advantages that the determination speed is fast, the environment in the working box is controllable and the determination environment is flexible to master compared with the prior art.

The invention discloses a device and method for measuring thermal resistance of an MOSFET power module, and belongs to the technical field of semiconductor device thermal resistance measuring. A drain-source voltage (VDS) and a drain-source current (IDS) of an MOSFET saturation region in the MOSFET power module are mainly used as temperature-sensitive parameters to measure junction temperature (TJ) of the MOSFET power module. The method comprises the following steps: firstly, establishing a three-dimensional relation curve cluster of VDS-IDS-TJ during a thermal resistance test of the MOSFET power module; comparing the three-dimensional relation curve cluster through the VDS and the IDS applied when the device works normally to obtain the TJ of the module; meanwhile, collecting casing temperature (TC) through a pressure spring type thermocouple; and finally, calculating the thermal resistance of the module through a theoretical formula. According to the method, the problem that the junction temperature of the MOSFET and the thermal resistance of the module cannot be measured due to the existence of an anti-parallel freewheel diode in the MOSFET power module is effectively solved.

The invention relates to a fiber heat conductivity determination method. The method includes: uniformly winding or adhering to-be-tested fibers to form test samples with N different arrangement angles, sequentially determining heat conductivity of the test samples and processing data. Compared with the prior art, the fiber heat conductivity determination method has the advantages that test principle simplicity and convenience in sampling are realized, internal structures of the samples are undamaged, test stability is achieved, integral distribution of fiber heat conductivity in different fiber directions can be directly reflected, the problem of failure in clear reflection of corresponding relation between each directional structure of fibers and heat conductivity in the prior art can be solved, heat conductivity test of heterogeneous or anisotropic materials according to a hot-wire method is realized, and advantages and disadvantages of fiber heat conductivity can be assessed comprehensively.

The invention relates to a device for testing reliability of a safety belt and a binding system of a baby carriage. The device comprises a directly-driven motor (DDR), an intelligent driver, a set ofhigh-speed silent screws, a set of linear bearing guide rods and a pair of quick-fixing fixtures (upper and lower fixtures), an S double-connection hole type force measurement sensor (a foil gauge type sensor), an amplifier and a data processing system are utilized to complete measurement, upper and lower limit positions of the device are respectively provided with a proximity switch, the equipment is guaranteed not to carry out over-travel operation, safety of equipment operation and testers is guaranteed, a man-machine dialogue mode is employed, so the force value and time and the repeated experiment frequency in the pulling process can be accurately guaranteed. The device is advantaged in that artificial interference is eliminated, data confirmation is directly utilized, and detection accuracy and efficiency are greatly improved.

The invention aims to provide a test device for assessing the drag reduction effect of a bionic jet flow surface revolution body wall surface and a test method. The test device comprises a pool, a slide block, a stepping motor and a pump. The stepping motor is connected with the slide block and drives the slide block to move, the slide block is connected with a revolution body wall surface model through a connection rod, the revolution body wall surface model is arranged in the pool, a jet flow pipeline is arranged in the revolution body wall surface model, and the revolution body wall surface model is provided with a jet flow hole and a jet flow hose. The jet flow hole and the jet flow hose are respectively communicated with the jet flow pipeline, the jet flow hose is connected with the pump through the jet flow pipeline, the jet flow pipeline is provided with a valve and a flow meter, and the pump is communicated with the pool. The revolution body wall surface model comprises a smooth surface revolution body wall surface model and a bionic jet flow surface revolution body wall surface model. The test device can test the drag reduction effect of the bionic jet flow surface revolution body wall surface, the drag reduction effect of a non-smooth surface revolution body wall surface structure and the drag reduction effect of a surface coating, and is easy to operate, and accurate in test result.

The invention relates to an electronic device junction temperature measurement method and device, belongs to the cover plate junction temperature measurement technology field and mainly utilizes the principle that the internal atmosphere of a device expands with temperature change to cause deformation of a device cover plate to obtain the junction temperature inside the device. The method comprises steps that firstly, the device in a non-working condition is heated, deformation of the device cover plate at each temperature point is monitored by a laser interferometer, so the one-to-one correspondence relationship between the heating temperature (the device junction temperature) and deformation of the device cover plate is obtained; secondly, deformation of the device cover plate is monitored under the working condition of the device and is compared with deformation of the device cover plate under the non-working condition of the device, and the junction temperature of the device can beobtained. The method is advantaged in that the junction temperature of discrete devices, integrated circuits and other devices can be effectively measured, unique advantages are realized compared with junction temperature measurement methods in the prior art, good practical value and economic benefits are realized, and the method is suitable for promotion and application.

The invention relates to a device for testing reliability of a safety belt and a binding system of a baby carriage. The device comprises a directly-driven motor (DDR), an intelligent driver, a set ofhigh-speed silent screws, a set of linear bearing guide rods and a pair of quick-fixing fixtures (upper and lower fixtures), an S double-connection hole type force measurement sensor (a foil gauge type sensor), an amplifier and a data processing system are utilized to complete measurement, upper and lower limit positions of the device are respectively provided with a proximity switch, the equipment is guaranteed not to carry out over-travel operation, safety of equipment operation and testers is guaranteed, a man-machine dialogue mode is employed, so the force value and time and the repeated experiment frequency in the pulling process can be accurately guaranteed. The device is advantaged in that artificial interference is eliminated, data confirmation is directly utilized, and detection accuracy and efficiency are greatly improved.

The invention relates to a single tower cable-stayed bridge model test system based on damage identification for the field of bridge test science. The test system comprises a single tower cable-stayed bridge model, a lever loading system and a cable tension test system, wherein the single tower cable-stayed bridge model comprises a main bridge, a main tower, a stayed cable, a support, a base and a support upright which are assembled together; the lever loading system comprises a gantry device, a lever device and a lintel device, wherein the gantry is transversely arranged above the main beam of the single tower cable-stayed bridge model, and the lintel device is placed on the main beam of the single tower cable-stayed bridge model; and the cable tension test system comprises an anchoring screw, a leveling block, a pressure ring sensor and an adjusting nut which are mounted in a cable beam anchoring area. According to the invention, model tests for the dynamic and static performance ofthe cable-stayed bridge and experimental studies on the damage identification method of the cable-stayed bridge structure can be performed; and moreover, real-time and quick measurement of the cable tension can be realized without changing the cable rigidity, and thus the problem of difficult measurement of cable tension in the cable-stayed bridge model is solved.

The invention discloses a device for testing output displacement of IPMC (ion-exchange polymer metal composite) linear drive unit and a method for testing the output displacement. The device is characterized in that both ends of a horizontal square baseboard are respectively fixed with a support base, two smooth sliding rails pass through both ends of each support base, the horizontal section of an inverted T-shaped sheet is arranged on the bottom side of each sliding rail, the vertical section of the inverted T-shaped sheet is arranged between said two sliding rails, one end of the IPMC linear drive unit to be tested is connected with the inside of one support base, the other end is connected with the inverted T-shaped sheet, an L-shaped bracket is installed on the support base connected with the IPMC linear drive unit, a first laser displacement sensor is fixed to the L-shaped bracket, and a second laser displacement sensor is installed on the other support base. The device is used for testing displacement of the IPMC linear drive unit, so that the regular linear movement of the IPMC linear drive unit can be realized and the experimental measurement requirements can be met; according to the device and the method, the testing principle is simple and visualized, the displacement value of the IPMC linear drive unit can be measured and the measurement result is reliable.

Provided are a device and method for testing an ice suppression effect of a salinization matter asphalt mixture. The device comprises a mainframe control device, a testing device and a test piece placing device for placing a test piece having formed ice through an icing device. The test piece placing device is arranged on the testing device, and the mainframe control device is connected with the testing device. The test piece icing device comprises a baffle and a test piece groove which are connected, the baffle is arranged on the test piece groove. The test piece icing device enables semicircular ice layers with required thicknesses to be frozen between two sides of intermediate standard Marshal test pieces in 3 standard Marshal test pieces and standard Marshal test pieces on the two sides. The device is simple in structure, and the ice suppression effect can be tested accurately. The device is simple in testing principle, easy to manufacture, simple and convenient in determination operation, economical and practical, and the problems that an existing ice suppression effect testing method is low in efficiency, poor in precision and large in human factor influence are solved.

The invention relates to a device and method for determining a molecular diffusion coefficient of a multi-component gas-liquid system in a rock core. The device mainly comprises an inlet pump, a confining pressure pump, a pressure returning pump, an intermediate container, a rock core clamper, an oil-gas two-phase separator, a pressure sensor and a computer, wherein one end of the intermediate container is connected with the inlet pump; thee other end of the intermediate container is connected with the rock core clamper; the rock core clamper is connected with the pressure return pump, the confining pressure pump and the oil-gas two-phase separator; and two ends of the rock core clamper are connected with the pressure sensor and the computer. The method comprises the following steps of: transferring an oil sample and a gas sample into the rock core through the inlet pump; contacting an oil phase with a gas phase to generate diffusion and cause the reduction of the gas phase pressure; monitoring the pressure change of a gas phase zone; after the gas and liquid reach the balance, enabling the drained fluid in the rock core to enter the oil-gas two-phase separator; and analyzing and testing the gas phase composition and the property change. The device and method disclosed by the invention are reliable in principle and simple and convenient in operation; and the molecular diffusion coefficient of each component of the multi-component gas-liquid system in real rock core in the gas phase and oil phase can be determined under different temperature and pressure conditions of an oil reservoir and reasonable base data is provided for quantitatively evaluating the influence on the improvement on the recovery ratio caused by a molecular diffusion effect.

The invention discloses a method for testing the interlaminar tensile strength of a 3D printed concrete member. The method comprises the steps of placing test pieces between brackets, and placing a pressure head on one test piece; enabling the pressure head to be in contact with a pressure head of a universal material testing machine, starting to press down, and measuring force F during fracture;and according to the area S of the crossed part of the two test pieces, obtaining the tensile strength Pten of the 3D printed test piece, namely, indicating that Pten = F / S. According to the testing device provided by the invention, grooves are formed in the parts, in direct contact with the test piece, of the brackets, in order to concentrate force during testing on the crossed part of the two test pieces, so that a test error is reduced; and roll balls are further arranged on the brackets, so that the test pieces can be prevented from being stuck in a testing process. According to the testing device and method provided by the invention, the axial tensile strength of the 3D printed concrete member can be obtained directly; the related problems that the stress direction is not clear, the fracture surface is not controllable and the like in a pull-off method are solved; the success rate of testing is greatly improved; the testing principle is simple and clear; and the reliability is high.

The invention discloses a differential pressure flow testing device for an electromagnetic valve of an automobile composite braking system. The device comprises a test valve block and a pressure source, the test valve block is used for mounting a test electromagnetic valve; the test valve block is provided with a low-pressure oil port and a high-pressure oil port; the pressure source is communicated with the high-pressure oil port to provide high-pressure oil for the test valve block; the low-pressure oil port of the test valve block is communicated with a load component, the low-pressure oilport and the high-pressure oil port are respectively connected with a pressure sensor, the low-pressure oil port is further connected with a flow meter, and the flow meter and the pressure sensors arerespectively and electrically connected with an oscilloscope. The flow and pressure difference relation curve generated by the flow of the low-pressure port of the electromagnetic valve along with the pressure change of the high-pressure port can be quickly obtained, and the influence of the difference of the mesh number of the filter screen on the flow and pressure difference curve of the electromagnetic valve can be tested when the same electromagnetic valve structure is adopted.

The invention discloses a concrete raw material chlorine ion content determination method, which comprises the following steps: adding a to-be-determined concrete raw material into a nitric acid solution, and heating for 1-2 minutes; accurately adding excessive silver nitrate solution, stirring and heating to precipitate all chlorine ions in the raw material in the form of silver chloride; filtering to remove silver chloride precipitates and undissolved raw materials to obtain supernatant liquid; preparing silver ion standard solutions with different concentrations, and establishing a standard curve with the concentration as the horizontal coordinate and the electric signal value CPS as the vertical coordinate by using an inductively coupled plasma emission spectrum; and determining the concentration of silver ions in the clear liquid by using an inductively coupled plasma emission spectrum and the standard curve, and obtaining the content of chlorine ions in the concrete raw material through a calculation formula. The method is suitable for concrete cement, mineral admixtures, sand, stone, additives and other raw materials, and the testing method is simple and easy to operate.

The invention provides a gallium-based liquid alloy-based sphygmomanometer and a blood pressure calibration method, which relate to the technical field of medical equipment, and specifically use a gallium-based liquid alloy column as a pressure-sensitive liquid for blood pressure testing to measure the blood pressure of a human body; The capillary length cooperates with the pressure control chamber to control the pressure of the sphygmomanometer, realizes the precise control of the gallium-based liquid alloy column, improves the measurement accuracy and shortens the length of the glass capillary while preventing the gallium-based liquid alloy from being oxidized; the sphygmomanometer and the The proposal of the blood pressure calibration method can greatly reduce the society's dependence on harmful mercury metals, solve the problems of poor measurement accuracy of electronic thermometers, and is expected to be greatly popularized and applied.

The invention provides a sensor for identifying a tubing coupling, which comprises a mounting base sleeved and fixed with a limiting sleeve in the circumferential direction, a hole is formed in the middle of the mounting base, a sensor mounting seat is arranged in the hole, a plurality of Hall sensors are distributed and fixed on the sensor mounting seat in the circumferential direction, and a plurality of grooves corresponding to the Hall sensors are formed in the outer side of the mounting base in the circumferential direction. Each groove is internally and correspondingly provided with a movable switch, one end of each movable switch penetrates through the limiting sleeve and extends to the outer side of the limiting sleeve, the other end of each movable switch is provided with a limiting shoulder so as to be clamped in the corresponding groove in a limiting mode, a spring is arranged between each movable switch and the bottom of the corresponding groove in a pressing mode, and magnetic steel is further fixed to the other end of each movable switch. The technical problem that a plunger type testing instrument recognizes the tubing coupling is solved. Belongs to the technical field of gas well underground testing instruments.

The invention discloses a capacitance measuring method based on the principle of electrostatic self-excited vibration, which comprises a high-voltage DC power supply, positive and negative electrode plates arranged in parallel, conductive microbeams, insulating supports, sampling resistors, capacitance to be measured, and a signal collector. The conductive micro-beams are fixed on the insulating support and placed in the middle of the positive and negative electrode plates. The positive and negative electrode plates are respectively connected to the positive and negative electrodes of the high-voltage DC power supply. One side of the sampling resistor is connected to the negative electrode plate and the other side is grounded. The capacitor to be measured is connected to the Between the root of the conductive microbeam and the negative pole of the power supply. When high-voltage direct current is applied to the positive and negative electrode plates, the conductive microbeams excite self-excited vibrations in the middle of the electrode plates, and the signal collector measures the pulse voltage at both ends of the resistance. The pulse voltage amplitude is linearly related to the capacitance to be measured. The magnitude of the pulse voltage can be calculated to obtain the size of the capacitance to be measured. The capacitance testing method proposed by the invention has simple principle and high measurement precision, and is suitable for measuring tiny capacitance values ​​in the pF order.

The invention provides a sphygmomanometer based on gallium-based liquid alloy and a blood pressure calibration method, relates to the technical field of medical equipment, and particularly relates to a sphygmomanometer using a gallium-based liquid alloy column as pressure sensing liquid for blood pressure testing to measure the blood pressure of a human body. A system for controlling the pressure of the sphygmomanometer by adjusting the length of a glass capillary tube and matching with a pressure control cavity is provided, so that the gallium-based liquid alloy column is accurately controlled, the gallium-based liquid alloy is prevented from being oxidized, the measurement precision is improved, and the length of the glass capillary tube is shortened. According to the sphygmomanometer and the blood pressure calibration method, dependence of society on harmful mercury metal can be greatly reduced, the problem that an electronic thermometer is poor in measurement precision is solved, and the sphygmomanometer and the blood pressure calibration method are expected to be widely applied and popularized.