58results about How to "Precise size adjustment" patented technology

The invention discloses a low-frequency ultrasonic secondary atomizing spraying head controlled in an electromagnetic mode. The low-frequency ultrasonic secondary atomizing spraying head comprises a nozzle. A liquid inlet hole is formed in the nozzle and communicated with one end of a liquid outlet hole. A trapezoidal nozzle groove is formed in the tail end of the nozzle and provided with a trapezoidal secondary atomizing moving body. The other end of the liquid outlet hole is communicated with the trapezoidal nozzle groove. An iron core and the trapezoidal atomizing moving body are bonded together. A coil winds around the iron core which is covered with a protecting cover. The protecting cover and the trapezoidal secondary atomizing moving body are bonded. One end of a stop block supports the trapezoidal secondary atomizing moving body. A sponge is stuffed between the stop block and the trapezoidal secondary atomizing moving body and bonded to the stop block. The other end of the stop block is welded to the nozzle. Currents flowing into the coil are changed by adjusting a circuit, electromagnetic force can be adjusted accurately, the distance between the trapezoidal nozzle groove and the trapezoidal secondary atomizing moving body is controlled accurately, and therefore the size of generated mist drops can be accurately controlled.

The invention provides a green synthesis method of a cadmium selenide nano-cluster and a cadmium selenide nanocrystal with controllable size. In the method, a series of low toxic/economical ligands are adopted, a selenium elementary substance and cadmium oxide dispersed in a non-ligand solvent are taken as precursors, and the cadmium selenide nano-cluster and the cadmium selenide nanocrystal are synthesized in the non-ligand solvent. The size can be adjusted within 0.7nm-13nm by adjusting the proportion of the ligands and the precursors. The obtained nanocrystal has high crystallinity and narrow size distribution fwhm which equals 25 plus or minus 2nm, relatively high fluorescence quantum efficiency which is 5%-38%, and a fluorescence emission spectrum can be adjusted within 450nm-690nm.

The invention relates to the technical field of nanomaterial preparation and particularly relates to a method for preparing a high density porous two-dimensional molybdenum disulfide nanosheet. The method comprises preparing an ordered aluminum nanometer hole AAO array template, directly forming a single layer of MoS2 nanosheets on a SiO2/Si base through a CVD method, transferring the ordered aluminum nanometer hole AAO array template to the single layer of MoS2 nanosheets to obtain a MoS2 nanosheet sample, transferring the MoS2 nanosheet sample into an ion etching chamber, carrying out etching, bombarding the MoS2 nanosheet sample, and removing the template of the MoS2 nanosheet sample to obtain the high density porous two-dimensional molybdenum disulfide nanosheets. The method can introduce a boundary-like structure to the base surface of the two-dimensional MoS2 to increase the number of active sites, can directly form a single layer of MoS2 on the SiO2/Si base, prevents MoS2 transferring and prevents a MoS2 loss during the transferring.

The invention discloses a novel tunnel lining segment mold. The novel tunnel lining segment mold comprises a bottom mold body, end mold bodies symmetrically arranged on the two sides of the bottom mold body and side mold bodies symmetrically arranged at the top of the bottom mold body. The bottom ends of the side mold bodies and the bottom ends of the end mold bodies are connected with the bottommold body through hinges, the side mold bodies and the end mold bodies are positioned on the bottom mold body through adjustable conical positioning devices, the side mold bodies and the end mold bodies are positioned through conical positioning devices, the side mold bodies, the bottom mold body and the end mold bodies are locked through locking devices, and mold starting devices are arranged between the side mold bodies and the bottom mold body as well as between the end mold bodies and the bottom mold body. The novel tunnel lining segment mold is accurate in positioning, stable in structureand high in precision, no clearing dead corners exist, and the novel tunnel lining segment mold can adapt to attachment type vibration and improve product quality.

The invention discloses a test piece clamping device for a large-diameter split Hopkinson pressure bar. The test piece clamping device comprises a fixing end and a sliding end, wherein the fixing endcomprises a fixing sleeve; the fixing sleeve is sleeved with a fixing ferrule; the fixing ferrule is provided with a plurality of fixing holes; the sliding end comprises a sliding sleeve; the slidingsleeve is sleeved with a sliding ferrule through a plurality of sliding chutes which are formed uniformly; slide blocks which are matched with the sliding chutes are fixedly arranged on the inner wallof the sliding ferrule; the sliding ferrule is provided with positioning holes in a penetrating way at positions corresponding to the slide blocks; positioning parts are arranged in the positioning holes; the sliding ferrule is provided with a plurality of connection holes; the connection holes and the fixing holes are connected with the two ends of elastic elements respectively. By adopting thetest piece clamping device, the problems of insufficient support reliability and low positioning accuracy in a test piece clamping device in the prior art can be solved. The test piece clamping devicehas the advantages of high reliability, low randomness, high universality, easiness in disassembly and assembly, wider pre-clamping force adjusting range and high applicability, and can be flexibly adjusted and assembled according to the size and strength of a test piece.

The invention relates to a synthesis method and application of a pore-diameter-adjustable Co-based MOF material with a nucleic acid screening function. The synthesis method comprises the following steps of: (1) respectively synthesizing organic ligands II, III and IV of which the chain lengths are progressively increased as shown in the following formula, (2) respectively preparing the same topological structure by selecting metal Co and the organic ligands II, III and IV to obtain MOFs materials of which the pore diameters are progressively increased, and (3) activating the prepared MOFs material, so as to obtain a Co-based MOF material, namely Co-IRMOF-74-II, Co-IRMOF-74-III and Co-IRMOF-74-IV. The synthesized MOF material is suitable for rapid separation of various types of nucleic acidmolecules with secondary structures and has universality, and MOF materials with different pore sizes are selected according to different types of separated nucleic acid structures.

The invention discloses a precise control circuit of an electro-hydraulic servo valve and a gas turbine generator set. According to the precise control circuit of the electro-hydraulic servo valve, alatch circuit is used for carrying out data latching on a control signal input by an external control device, then a D/A conversion circuit converts the digital quantity control signals input by the external control device into analog quantity control signals, finally a negative feedback control circuit receives the analog quantity control signals transmitted by the D/A conversion circuit and precisely adjusts the current input to the electro-hydraulic servo valve, so that the size of the opening of a valve is accurately adjusted so as to accurately control the amount of oil flowing into the generator set, and finally the purpose of accurately controlling the rotating speed of the generator set is achieved. According to the precise control circuit, the precise control circuit of the electro-hydraulic servo valve can accurately control the electro-hydraulic servo valve, so that the acceleration, deceleration and pressure stabilization operation of the generator set can be realized. In addition, the accurate control circuit of the electro-hydraulic servo valve is mainly applied to the gas turbine generator set.

The invention discloses a side-feed type cyclone which can precisely adjust and control the flow velocity of the liquid-phase swirl on the outside. The sealing cavity formed between the jacket and the swirl tube; the upper section of the swirl tube is provided with an internal thread to match the external thread of the flow rate regulating valve and seal the top end, and the middle section is tangential to the inside of the outer jacket and the wall of the swirl tube. On its inner circle, a number of rectangular slits are evenly arranged, and the lower section extends to the outside of the outer jacket; the flow rate regulating valve and part of the swirl tube are arranged outside the outer jacket, and the front section of the flow velocity regulating valve is a cylinder, and the rear section is provided with external threads, respectively. The inner circle of the swirl tube is matched with the inner thread; the size of the tangential slit of the swirl is adjusted through the rotary flow rate regulating valve to realize the adjustment and control of the liquid phase swirl flow rate and the residence time in the swirl tube, which is suitable for solid/liquid cyclone separators Solid and liquid separation of different properties in applications and physical and chemical reactions of different properties in tubular reactor applications.

The invention belongs to the technical field of processing and preparation of silicon nanometer holes, and particularly relates to a method for adjusting diameter of a silicon nanometer hole. The method comprises the steps as follows: measuring the diameter of the silicon nanometer hole; and calculating the difference delta of the diameter and an expected value, if the diameter is greater than the expected value, a device provided with the silicon nanometer hole is heated and oxidized to ensure that the thickness r of silicon that is oxidized equals to (delta/2)*(44/56), then detection is carried out to ensure that whether the diameter of the silicon nanometer hole reaches the expected value or not until the a hole with an expected diameter is obtained, however, if the diameter is smaller than the expected value, the device provided with the silicon nanometer hole is heated and oxidized to ensure that the thickness of silicon that is oxidized equals to delta/2, then a generated silicon dioxide layer is corroded by hydrofluoric acid solution, and finally then detection is carried out to ensure that whether the diameter of the silicon nanometer hole reaches the expected value or not until the a hole with an expected diameter is obtained. By adopting the method, the size of the silicon nanometer hole can be adjusted accurately, and repeated adjustment can be realized, so that design requirements can be met conveniently.

The invention discloses a Crowbar device for low voltage ride-through of a wind generator set and a control method of the device. The device comprises an uncontrolled rectifier bridge G, a controllable component QS, a controllable component QX and a bleeder resistor RC, wherein an input end of the uncontrolled rectifier bridge G is connected with A, B and C phases on a rotor side of a double-fed asynchronous generator; the controllable component QS and the controllable component QX are connected with an output end of the uncontrolled rectifier bridge G in series; one end of the bleeder resistor RC is connected with a connection point of the controllable component QS and the controllable component QX; and the other end of the bleeder resistor RC is connected with a positive output end or a negative output end of the uncontrolled rectifier bridge G; The device is simple in structure and lower in cost, and solves the problems that the existing Crowbar is complicated in structure and higher in cost.

The invention discloses an interactive training curriculum management system which comprises an intelligent terminal, a data server, a network server and a cabinet. The cabinet comprises a cabinet body, at least two separating plates, an air inlet, a flow deflector, an air outlet, air outgoing holes and at least one wireless temperature sensor, wherein the cabinet body comprises a front door plate, a rear door plate, a top plate, a bottom plate, a left side plate and a right side plate; the separating plates are arranged in the cabinet body horizontally, and are separated from the front door plate for certain distance to form a cold air cavity; the air inlet is arranged in the base plate and communicates with the cold air cavity correspondingly, and is provided with a sliding cover plate; the flow deflector is arranged over the air inlet, one end of the flow deflector is connected to the side, close to the front door plate, of the bottommost separating plate, and the other end of the flow deflector is connected to the side, close to the rear door plate, of the air inlet; the air outlet is arranged in the top plate; the air outgoing holes are arranged in the rear door plate; and the wireless temperature sensor is mounted in the bottom side of the separating plate. According to the interactive training curriculum management system of the invention, the cabinet realizes cooling in a downward blowing manner, and the energy utilization efficiency can be improved effectively.

The invention discloses a three-ring fire valve core and relates to the technical field of gas stove adjusting valves. Specifically, the three-ring fire valve core comprises a fixing base and a conical vent valve core. A clamping and installing groove is formed in the middle of the fixing base. A sealing outer edge face is arranged on the outer surface of the conical vent valve core. The conical vent valve core is located above the fixing base. A connecting flange is arranged on the inner side of the conical vent valve core. A clamping flange is arranged above the connecting flange. A connecting hole is formed above the clamping flange. A gas inlet is connected above the connecting hole. A valve core lower portion gas outlet is formed in the middle of the conical vent valve core. Accordingto the three-ring fire valve core, total supply of fuel gas is achieved through the gas inlet, the whole device is installed on the fuel gas adjusting valve through the fixing base, fuel gas is supplied through the gas inlet in the bottom of the fixing base, the gas inlet is connected with the connecting hole in a communicating manner, meanwhile, the gas inlet and the fixing base are located on the same vertical line, and passing and supply efficiency of the fuel gas can be kept conveniently.

The invention relates to a device integrated with a junction field effect transistor and a manufacturing method thereof. The JFET region of the device comprises: a JFET source, a metal electrode of the JFET source, composite well region structures and a JFET metal gate, wherein the JFET source is of a first conductive type; the metal electrode is formed on the JFET source and is in contact with the JFET source; each composite well region structure is of a second conductive type, is arranged within a first conductive type region and comprises a first well and a second well in the first well, the ion concentration of the second well is greater than that of the first well, the composite well region structure is formed on each of two sides of the JFET source, and the JFET source extends transversely into the first well and the second well; and the JFET metal gate is arranged on the composite well region structures on two sides of the JFET source. By using a composite channel formed by a composite well region consisting of the first well and the second well, the channel depletion capability is enhanced, and the pinch-off voltage stability is strengthened. At the same time, the pinch-offvoltage can be accurately adjusted by adjusting the distance between the composite channels to meet different circuit application occasions.

The invention discloses a circuit which is applied to a relaxation oscillator and is capable of realizing precise frequency modulation. Compared with a traditional frequency modulation of the relaxation oscillator, the circuit has the advantages that through utilization of errors imported by multiway feedback voltages, the problem that a structure of the relaxation oscillator is difficult to realize precise frequency modulation is skillfully solved, and a relaxation structured oscillator, instead of a crystal oscillator, can even be applied to some circuits having relatively harsh frequency precision demands.

The invention discloses a four-roller mandrel pipe mill which comprises a tunnel type memorial archway, rolling racks arranged along the central axis of the tunnel type memorial archway in sequence, roller fittings located inside the rolling racks and a transmission system used for driving all the roller fittings to rotate. Each mill rack is provided with four sets of roller fittings, all the roller fittings are respectively connected to a set of roller clearance adjusting device used for adjusting the roller clearance, the roller clearance adjusting device is fixed on the tunnel type memorial archway, and each rolling rack is further provided with a rolling changing device used for allowing the corresponding rolling rack to move back and forth in the central axis direction of the tunnel type memorial archway. Four rollers are driven independently, the speeds in the peripheral direction of steel pipes are good in consistency, deformation is even, a hole pattern is sealed better, the wall thickness precision of products is improved, rolling defects are reduced, and the specification range of products capable of being rolled is enlarged.

The invention relates to a discharging mechanism for a steaming robot. The discharging mechanism comprises a stock bin and a distributor, wherein the distributor is located under the stock bin; the stock bin is equipped with a discharging port; the discharging port is shielded by a plurality of shielding sheets; the size of the discharging port can be adjusted by changing the size of the area of the discharging port shielded by one, two or more shielding sheets. According to the discharging mechanism for the steam-filling robot provided by the invention, a plurality of shielding sheets are arranged at the discharging port and the size of the discharging port can be adjusted by vertically drawing the shielding sheets, so that the fine adjustment can be realized, the area of the discharging port shielded by each shielding sheet can be adjusted and the function of finely adjusting the size of the discharging port can be achieved; the discharging ports on different parts can be differently arranged according to the requirement of the steam-filling material distribution, so that the different discharging volumes can be controlled; for example, the part close to the inner wall of the steam barrel can discharge more materials than the interior of the steam barrel, so that the lower inner and higher outer of the material distribution surface can be realized; the steaming effect can be promoted; the quality of the white spirit can be further increased.

The invention discloses an injection mold capable of adjusting the length of a pipe fitting. The injection mold comprises a fixed mold plate, a movable mold plate and a mold core. A first cavity blockis arranged on the fixed mold plate, a second cavity block is arranged on the movable mold plate, and the first cavity block and the second cavity block form a tubular cavity with an opening. The mold core is arranged in the tubular cavity in a core pulling manner from the opening, the outer wall of the mold core, the inner wall of the first cavity block and the inner wall of the second cavity block form a tubular forming cavity, the mold core is sleeved with an adjusting sleeve, and the inner end of the adjusting sleeve stretches into the tubular forming cavity. An axial adjusting and fixingdevice is arranged at the opening of the tubular cavity. After the adjusting sleeve slides to a required position on the mold core, the adjusting sleeve is fixed to the axial adjusting and fixing device so as to change the length of the tubular forming cavity. According to the scheme, adjustment is convenient, direct operation can be conducted on a machine table, size adjustment is accurate, andformed products do not need to be cut.