55results about How to "Improve pressure sensitivity" patented technology

The invention discloses an IVB-family element modified CaCu3Ti4O12-based pressure-sensitive material and a preparation method thereof. The general formula of a chemical composition of the pressure-sensitive material is CaCu3Ti4-xAxO12, wherein A is one or the composition of several of IVB-family elements in the periodic table of chemical elements and is not Ti, and x is equal to 0.002-2. The preparation method comprises the following steps of: proportioning calcium carbonate, copper oxide, titanium dioxide, zirconium dioxide and hafnium dioxide in a stoichiometric ratio of the CaCu3Ti4-xAxO12, wherein, x is equal to 0.002-2; A is one or the composition of several of the IVB-family elements in the periodic table of chemical elements and is not Ti; then carrying out the processes of ball milling, calcining, secondary ball milling, pelleting, shaping, rubber discharging and high-temperature sintering to finally prepare CaCu3Ti4O12-based ceramic with good pressure-sensitive characteristic. The invention effectively improves the pressure-sensitive characteristic of the ceramic, reduces the leakage current thereof, and simplifies the preparation process while holding the high dielectric performance of the pressure-sensitive ceramic, thereby making the ceramic meet commercial demands.

The invention provides a full-nanofiber electronic skin which comprises an upper nanofiber membrane, a middle nanofiber membrane and a lower nanofiber membrane which are a contact electrification layer, a middle electrode layer and a bottom supporting layer respectively. The contact electrification layer and the bottom supporting layer are both nanofiber membranes made of biodegradable materials.And the middle electrode layer is a nanofiber membrane with a sterilization function and is electrically connected with the ground or other conductors. The electronic skin is provided with a pluralityof layers of staggered nanofiber networks and a large number of three-dimensional micro-nano hierarchical pores, so that the electronic skin has air permeability, high output, high pressure sensitivity and antibacterial property.

The invention belongs to the technical field of detonation pressure transient measurement, and discloses a compact detonation pressure measuring system based on Bragg fiber grating. The compact detonation pressure measuring system based on Bragg fiber grating includes a broadband light source, an optical isolator, a first optical coupler, a second optical coupler, a third optical coupler, a pressure FBG sensing grating embedded into the tested explosive, a chirped matching grating embedded into the tested explosive, an M-Z unbalanced interferometer, a photoelectric detection circuit, a analog-to-digital conversion circuit, a DSP processor and a fiber spectrometer. The compact detonation pressure measuring system based on Bragg fiber grating senses the detonation pressure by means of the frequency shift effect of the pressure FBG sensing grating on the incident light, and eliminates the optical interference signal which is generated from explosion wave through the chirped grating matching the emission bandwidth, so as to improve the signal to noise ratio. And at the same time, through the fiber spectrometer, the compact detonation pressure measuring system based on Bragg fiber grating calibrates the relation between the sensor pressure and the phase, and compensates and calibrates the initial pressure of the sensor. The compact detonation pressure measuring system based on Braggfiber grating utilizes the compact structure, and can be widely applied to the detonation pressure measurement field.

The invention provides a pressure sensing device with high sensitivity, which comprises a wideband light source, a circulator, a sensing head and a spectrum analyzer, wherein the sensing head is composed of a corrosion multimode fiber and an ultraviolet adhesive. The pressure sensing device with high sensitivity is characterized in that after the multimode fiber end surface is corroded, a conical cavity is obtained, the ultraviolet adhesive is penetrated in the conical cavity, and an air cavity coated by the ultraviolet adhesive is formed in the conical cavity. The circulator receives light from the wideband light source and transmits the light to the sensing head, the sensing head reflects the light back to the circulator, the light is then transmitted to the spectrum analyzer via the circulator, a similar Fabry-Perot interferometer is formed, and wavelength drift of a reflection spectrum characteristic peak is measured, and thus, the numerical value of a tested environmental parameter can be calculated. The pressure sensing device with high sensitivity is applicable to measurement on various environmental parameters, particularly, pressure measurement, and has the advantages of compact structure, simple manufacturing, high sensitivity, wide measurement range, and low cross sensitivity.

The invention discloses a heat exchanging method of liquid natural gas (LNG) cold energy used for a high-temperature-level cold energy user. According to the method, in the process of LNG entering tube passes of the upper portions of heat exchangers from an LNG storage tank, heat exchanging is achieved among the LNG, first refrigerant and nitrogen added into shell passes of the upper portions of the heat exchangers, and the temperature rises; the LNG passes through an air vaporizer and enters a natural gas pipeline network after the temperature rises; on the upper portions of the heat exchangers, the temperature of the first refrigerant and the nitrogen coming out of a refrigerant storage tank decreases to -40 DEG C-0 DEG C after heat exchanging is performed among the first refrigerant, the nitrogen and the LNG, and the first refrigerant and the nitrogen come into a liquid phase from a gas phase and enter the lower portions of the heat exchangers; the pressure PB of the nitrogen is determined through the formula (6) shown in the specification; the cooled first refrigerant achieves heat exchanging with second refrigerant on the lower portions of the heat exchangers, the temperature of the first refrigerant rises, the first refrigerant comes into a gas phase from the liquid phase and returns to the upper portions of the heat exchangers, and therefore a cycle is completed. Through using the usage amount of the nitrogen for changing the partial pressure of the refrigerant, the sensitivity of system operation is improved while the freezing point of the first refrigerant is lowered, and safety and stability in the heat exchanging process are guaranteed.

The invention discloses a method for a measuring sea water temperature profile based on an optical fiber Brillouin scattering principle. A Brillouin optical time domain reflection principle-based measurement system consists of a narrow line-width laser, an optical coupler, a pulse generator, an optical modulator, a circulator, an optical switch, a photoelectric detector, a Brillouin frequency shift detection unit and a sensing optical cable. The sensing optical cable used by the invention has a small size and sea water corrosion resistance, and is convenient to use. The measurement system hashigh reliability and high measuring sensitivity, can provide continuous temperature field distribution of the sea water profile, and is particularly suitable for real-time continuous measurement of the sea water temperature profile.

The invention relates to a sea urchin-like oxide-based composite film bionic pressure sensor, which includes a packaging layer, a flexible base, a sensitive film and an electrode, the flexible base is connected above and below the sensitive film, and the surfaces directly opposite to the flexible base above and below are covered There is a sea urchin-like oxide-based composite film, and the sea-urchin-like oxide-based composite film is connected with an external electrode. The sea urchin-like oxide-conductive material composite film is coated on the flexible substrate. On the one hand, the sea urchin-like metal oxide supports the conductive material and improves the deformation ability of the conductive material under pressure; on the other hand, the conductive material The material is coated on the surface of the sea urchin-like metal oxide, which makes up for the shortcomings of the sea urchin-like metal oxide such as poor electrical conductivity and high power consumption. Therefore, the combination of sea urchin-like metal oxides and conductive materials can make the sensor have the advantages of high sensitivity, low power consumption, simple preparation method, low cost, and easy mass production.

The invention discloses a mineralized hydrogel, a preparation method and application thereof, and belongs to the technical field of artificial skin. The mineralized hydrogel comprises the following raw material components: 3-6vol% polyacrylic acid, 0.05-0.15wt% chitosan and 18-22wt% amorphous calcium phosphate; the molecular weight of the polyacrylic acid is 100000, the chitosan The sugar is of medium molecular weight; the amorphous calcium phosphate is produced by 2-2.5 wt % of anhydrous calcium chloride and 5.5-6 wt % of disodium hydrogen phosphate dodecahydrate in the process of hydrogel formation. The synthesis method of the invention is simple, fast, mild and environmentally friendly, and the prepared mineralized hydrogel has flexibility, antibacterial properties and induction properties, so it has broad application in smart skin materials, artificial intelligence equipment, wearable devices and the like. application prospects.

The invention relates to a dynamic expansion oil pipe joint for low oil pressure. The dynamic expansion oil pipe joint mainly comprises an oil pipe joint body, and a driving block arranged in the oil pipe joint body, wherein multiple pressure bearing pieces are arranged in the driving block, and are communicated with a relatively slipping inclined surface mechanism; multiple pushing keys projected on the wall surface of the oil pipe joint body are arranged on the outer wall of the driving block; the surfaces of the pushing keys are inclined surfaces; when oil pressure is increased, the pushing keys are displaced, and drive a rubber ring coating the outer wall of the oil pipe joint body to expand so as to increase the binding force between the oil pipe joint and the oil pipe wall surface; and the pressure bearing pieces solve the problem that pushing blocks can be driven through higher oil pressure due to weak pressure bearing and movement sensitivity.

The invention discloses a flexible pressure sensor based on a polyimide substrate microstructure and a preparation method thereof. The flexible pressure sensor of the present invention comprises a lower flexible substrate, a force-sensitive structural layer and an upper flexible encapsulation layer; the lower flexible substrate is a polyimide film, and its upper surface has a raised microstructure array; the force-sensitive structural layer and the lower flexible substrate The upper surface is tightly bonded, which includes a lower electrode layer, a flexible piezoresistive material layer, and an upper electrode layer from bottom to top. The flexible piezoresistive material layer is a carbon-based nanoparticle / polymer piezoresistive material with piezoresistive properties; the upper flexible package The layer is closely attached to the upper surface of the force-sensitive structure layer to protect the sensor and waterproof. The invention prepares a flexible pressure sensor based on a polyimide substrate microstructure by adopting bottom-up micro-nano manufacturing technology, and has the advantages of high sensitivity, ultra-thin and ultra-light, simple process, easy array manufacturing and strong applicability.

The present invention provides a display panel and a display device. The display panel comprises electrode block groups; the electrode block group comprises at least two adjacent electrode blocks; each electrode block group is electrically connected to a connection unit; the connection unit is used for, in a pressure scanning phase, electrically connecting the capacitances consisting of each electrode block in the electrode block group and floating electrode layers to be the combined capacitance, and in a touch scanning phase and the display scanning phase, making each electrode block in the electrode block group be isolated from each other. In the pressure scanning phase, it is ensured that the difference between the electric capacity feed backed by the combined capacitance and the independent capacitance in an initial state phase, and the preset electric capacity is in a preset range, so that the initial electric capacity feed backed by the combined capacitance and the independent capacitance of the entire display panel is relatively average, then the signal to noise ratio of the pressure detection can be improved, implementation of initial electric capacity compensation in the panel can be facilitated, sensitivity of pressure sensing can be improved, and a relatively high pressure sensing effect of the display panel can be ensured.