33results about How to "With filtering effect" patented technology

The invention discloses a multiplexed volume holographic grating. The multiplexed volume holographic grating respectively records red, green and blue three holograms on the same dielectric layer by exposing for three times; volume holographic gratings formed by exposure of different wavelengths are the same in inclination angle and are different in period; by controlling exposure time, refractive index modulation depths corresponding to red, green and blue light after exposure accords with the relation that delta n red light is greater than delta n green light, and delta n green light is greater than delta n blue light, and peak diffraction efficiencies corresponding to the red, green and blue light after exposure are similar. The multiplexed volume holographic grating can effectively balance irradiating energy of red, green and blue light waves and avoid color offset.

The invention discloses an LED outputting narrow-band notch filtering light, and a preparation method thereof. According to the invention, a multi-layer waveguide structural layer is composited on the light-emitting surface of an LED chip and comprises a medium depletion layer, a composite grating layer and a medium protective layer; the composite grating layer is a metal/medium grating film layer which is formed by metal strips and medium strips at intervals; the medium depletion layer is positioned below the composite grating layer and is in direct contact with the light-emitting surface of the LED chip; the medium protective layer is above the composite grating layer and is in direct contact with the ambient environment or transparency electrode; and the thickness of each layer of the multi-layer waveguide structure layer, the grating duty cycle and the period parameter are designed to meet the condition of the resonance of the light waveguide mold transmission. According to the invention, a sub-wavelength metal/medium composite grating structure is directly integrated on the surface of the LED chip, and the LED per se has filtering effect; and compared with a traditional passive filter, the LED is a highly integrated active filtering light-emitting device.

Aiming at the problem of "screening first and pressing later" manure treatment process and equipment, it proposes septic grade change, manure sludge dehydration, manure fermentation, and manure water filtration; a suitable, reliable and economical anaerobic digestion facility for manure is disclosed. The facility has a septic tank composed of a septic tank and a septic valve, and the operation of the septic valve enters the fourth-stage or third-stage anaerobic digestion mode of manure; there is a manure ditch or a manure pipe, and the potential energy is used to send manure; there is also a filter The cylinder and pump/pipe can sink into the septic chamber to pump water, dehydrate the sludge into manure, and then dig out the manure and transport it out for accumulation and fermentation; the filter cartridge can also be covered with a filter cloth bag, and the filter cartridge can be sunk into the manure chamber , pump out clean water and send to rinse.

The invention discloses a building dense point cloud rapid reconstruction method based on PMVS. In an application scene of 3D reconstruction of buildings, the method uses the quasi-dense point cloud to replace the self-built sparse point cloud of a PMVS algorithm as a diffusion seed point. The main flow of the method of the invention comprises the following steps: first, an initial spatial triangular mesh model of the building is constructed, spatial interpolation diffusion, patch optimization and filtering, triangular mesh information updating and other operations are carried out to obtain accurate quasi-dense point cloud, and the quasi-dense point cloud is used to replace the self-built sparse point cloud of the PMVS algorithm as a diffusion seed point, and thus acceleration of the reconstruction process of the PMVS algorithm is realized. The method can effectively improve the operation efficiency of the PMVS algorithm. The method plays a certain filtering effect on the point cloud noise brought by natural landscapes and other non-building main body point cloud noise.

The invention belongs to the technical field of y-shaped filters, and particularly relates to a Y-type magnetic filter. The Y-type magnetic filter comprises a side barrel arranged on a side wall, wherein a barrel cover is arranged at the top of the side barrel; a cylindrical filter screen is inserted into the side barrel; at least one magnetic component is arranged on the internal surface of the barrel cover and located in the filter screen; the magnetic components comprise fixing bars made from nylon materials and magnetic blocks; the fixing bars are sleeved with the magnetic blocks; the magnetic blocks are of cylindrical structures with through holes in the middles and are made from plastic magnets; a non-asbestos gasket is arranged between the barrel cover and the upper surface of the side barrel for sealing; and the filter has a good effect of absorbing iron particulates and does not generate magnetic particulate pollution media.

The invention belongs to the technical field of optical fiber sensing, and particularly relates to a tunable optical-fiber filter. Two V-shaped groove serrate plates with long cycle and equal interval are used to apply stress to single-mode optical fibers so as to form a long-cycle grating. After the long-cycle grating is placed in a thermostatic chamber, temperature is changed through a thermostatic oven, and wavelength of filter wave is changed as needed. Since the two V-shaped groove serrate plates with long cycle and equal interval apply stress to the single-mode optical fibers after being fixed with screws, attenuation degree of light wave intensity is regulated on the condition of keeping the central wavelength of resonance wave constant, and filtering performance is improved. The tunable optical-fiber filter capable of changing wavelength of the filter wave and attenuation degree of light intensity simultaneously is simple in structure and has erasability.

The invention discloses an island detection method for a droop control grid-connected inverter. The method is implemented specifically according to the following steps: 1, a three-phase grid-connectedinverter main circuit system is built; 2, output active power and reactive power of the three-phase grid-connected inverter are calculated; 3, an improved P-f droop controller with disturbance k(f-f<g>)/s added is utilized to calculate reference output of voltage amplitude and phase; 4, difference between the reference voltage and phase and actual voltage and phase is calculated to obtain an error voltage value as reference input of an outer ring regulator, output of the regulator is reference input of inner ring current, difference between the reference input of the inner ring current and actual current is calculated to obtain an error current value as input of an inner ring regulator, and finally, an output modulation signal is obtained; and 5,the value of |d[delta][theta]/dt|=|k(f-f<g>)| is monitored in real time to perform island judgment. According to the island detection method for a droop control grid-connected inverter, on the basis of a traditional island monitoring droop improvement method, integration is added for the disturbance part, the amplitude of |d[delta][theta]/dt| is increased and stable amplitude is maintained, thereby avoiding island misjudgment.

A reactive power compensation device of no-load transformer based on high supply and high meter is composed of a main working compensation loop, a supplementary compensation loop and da isplay metering loop. The main working loop can not only achieve the effect of reactive power compensation, but also effectively avoids the harmonic resonance. Supplementary compensation circuit can improve the compensation precision of high voltage side of transformer. The invention makes up for the defect that the reactive power compensation of the load carried by the enterprise can not be switched on and offwhen the transformer is no load, improves the compensation precision and improves the power factor when the low voltage side of the transformer is no load. Whether or not the transformer is in a large load state or no load state, the power factor measured at the high-voltage side of the transformer can be kept above 0.9, so the power regulation fee penalty can be effectively avoided, and the power consumption cost of the enterprise is reduced.

The invention relates to the technical field of curtain type sewage treatment, and discloses curtain type sewage treatment equipment and a using method thereof.The curtain type sewage treatment equipment comprises a box body and a suction vacuum pump on one side of the box body, an external hose is installed at the upper end of the suction vacuum pump, a liquid inlet pipe is arranged on one side of the box body, and a liquid outlet pipe is arranged on the other side of the box body; supporting frames are symmetrically arranged at the upper end of the box body, hydraulic shafts are installed on one sides of the supporting frames, pressing plates are installed at the lower ends of the two hydraulic shafts, a filtering frame is installed in the box body, a limiting groove is formed in the top end of the filtering frame, a sealing cover plate is installed in the limiting groove, and a limiting inner groove is formed in the filtering frame. When sewage preliminarily enters an external pipeline and has more internal impurities, the filtering pipe is matched with the supporting base, so that the impurities in the sewage are filtered, the situation that the impurities flow into the subsequent process and the filtering load is increased is avoided, and the working intensity of a subsequent structure is relieved.

A method for preparing a diesel low temperature wax crystal disperser and the application of the disperser belongs to the field of disperser. The preparation method is as follows: mixing an organic carboxylic acid and an aliphatic amine or an aliphatic alcohol according to a quantity ratio of 1:1.5 to 3:1; taking toluene or xylene as a solvent, reacting for 2 to 5 hours at a temperature of 60 DEG C to 150 DEG C, steaming out the solvent to get the disperser. When reacting with aliphatic amine, a needed catalyst is a toluene sulfonic acid. The organic carboxylic acid is a p-tert-butylbenzoic acid or a mixture of dodecanoic acid, myristic acid, hexadecanoic acid and stearic acid according to a quantity ratio of 1:1.15:1.3:1.45. The carbon number of aliphatic amine or aliphatic alcohol is C3 to C8; a blending temperature of the disperser and the present sold diesel low temperature flow modifier is 50 DEG C to 120 DEG C; the quantity ratio is 1:1 to 1:4. The cooperation of the dispersers and the present domestic diesel low temperature flow modifier can more effectively reduce the cold filter plugging point of long distillate diesel and has a certain sensitivity to narrow fraction diesel.

The invention discloses an echo amplification circuit of a low-noise MEMS piezoelectric hydrophone. The echo amplification circuit mainly comprises an non-inverting amplification circuit and a voltagefollower circuit. The circuit is powered by an accurate voltage source. A proper static potential is provided for the non-inverting amplification circuit by using the follower circuit through resistance voltage division; by selecting an operational amplifier with low equivalent input noise voltage and low equivalent input noise current and reasonably selecting an external resistor, the echo amplification circuit has a certain filtering effect, meanwhile, the equivalent input noise of the circuit is reduced, and the signal-to-noise ratio of the signal is further improved. The circuit is convenient to adjust the static working point of the amplification circuit, the circuit is simplified by means of power supply of a single power supply, good in circuit stability, few in used devices, low in cost, convenient to connect with an external circuit due to the fact that input and output share the same interface, convenient to operate and certain in application value.

The invention provides an extra-high-voltage converter transformer with a filtering function. A making method of the extra-high-voltage converter transformer with the filtering function comprises thefollowing steps that S1, the converter transformer of an extra-high-voltage direct-current power transmission system serves as an object, and the magnetic circuit saturation condition and the harmoniccirculation condition of the converter transformer are taken into consideration, wherein a circuit magnetic circuit analysis structure of a single iron core column is included; and S2, the magnetic circuit distribution and a circuit structure of the converter transformer are taken into consideration, and a four-winding type converter transformer electromagnetic coupling circuit and an electromagnetic coupling circuit equivalent circuit model according to an extra-high voltage direct current power transmission operation scene. The extra-high-voltage converter transformer with the filtering function is suitable for an extra-high-voltage direct-current power transmission system, and has a harmonic filtering function while having voltage matching and electrical isolation functions of a commonconverter transformer, so the grid-side harmonic and reactive burdens of an existing extra-high-voltage direct-current power transmission project converter transformer are reduced, and the reliability of the extra-high-voltage direct-current power transmission project is improved; and thus, the investment of a grid-side alternating-current filter is reduced.