42results about How to "Improve launch stability" patented technology

The invention provides a cathode of a cold-cathode X-ray tube. The cathode of the cold-cathode X-ray tube comprises a cathode base and a grid electrode, wherein the cathode base is composed of an upper cylinder and a lower cylinder which are coaxially arranged, the section of the cathode base is in an inverted-T shape, a cathode bar through hole is formed in the central axis of the cathode base, a cathode bar is arranged in the through hole, the three-dimensional size of the cathode bar can be controlled, an electron emitter is arranged on a cathode head, the grid electrode is of an cup-shaped structure, an inverted-T-shaped groove which is matched with the cathode base is formed inside the grid electrode, the cathode base can be embedded in the groove of the grid electrode and does not make contact with the inner wall of the grid electrode, and a semi-conical electron transmission hole used for focusing electrons emitted by the cathode is formed in the center of the grid electrode. According to the cathode of the cold-cathode X-ray tube, the cold cathode made of carbon nanomaterials is used as the X-ray tube of an electron emission source, and preparation of the cathode and the emission area can be effectively controlled through the size of the cathode bar; the three-pole structure is adopted, a small focus point can be obtained through focusing of the grid electrode, and the resolution ratio of X-ray imaging is increased.

A method for improving performance of carbon nanotube film electronic field emission by electrophoresis deposit means includes plating transition metal film on conductive substrate material by physical gas phase depositing process, utilizing plated conductive substrate as cathode to deposit carbon nanotube film on said cathode through electrophoresis depositing process and carrying out annealing treatment on cathode deposited with carbon nanotube film for raising field emission current density.

The method comprises: setting the data electrode on the glass cathode baseboard; on the data electrode, setting the dielectric layer with a horizontal bar shape and perpendicular with the data electrode; on the dielectric layer, setting the row scanning electrode; on the row scanning electrode, setting the connection electrode parallel with the data electrode; at the gap between the connection electrode and the row scanning electrode, setting a field emission material with a certain resistance property; on the glass cathode base board and the dielectric layer, setting the supporter; on the supporter, setting a anode glass baseboard; on the lower surface the glass anode baseboard, setting the anode electrode; on the lower surface of the anode electrode, setting a fluorescent powder layer.

The invention relates to a field emission cathode structure with a current limiting resistive switching layer and a preparation method thereof, which belong to the technical field of field electron emission. A composite memristor material doped with metal ions is used as a resistive switching layer between each cathode emitter and a substrate in a field emission array cathode, and the resistive switching layer under each cathode emitter controls the migration of metal ions in the resistive switching layer by its own current change. The resistive switching layer is in a low-resistance state during normal emission of the cathode emitter. Under short-circuit or over-current emission, the resistive switching layer is switched to a high-resistance state. The different cathode emitters do not affect one another, and the maximum emission current of a single cathode emitter can be limited to restrain short-circuit or over-current emission. The field emission current limiting structure providedby the invention is simpler than the existing current limiting structure, and has low preparation cost. Because of the existence of the resistive switching layer, the emission stability of the fieldemission cathode is improved without affecting the field emission characteristic, and the field emission cathode structure is of great significance for improving the performance of the existing fieldemission cathode.

The method comprises: setting the data electrode on the glass cathode baseboard; on the data electrode, setting the dielectric layer with a horizontal bar shape and perpendicular with the data electrode; on the dielectric layer, setting the row scanning electrode; on the row scanning electrode, setting the connection electrode parallel with the data electrode; at the gap between the connection electrode and the row scanning electrode, setting a field emission material with a certain resistance property; on the glass cathode base board and the dielectric layer, setting the supporter; on the supporter, setting a anode glass baseboard; on the lower surface the glass anode baseboard, setting the anode electrode; on the lower surface of the anode electrode, setting a fluorescent powder layer.

The invention discloses a method for preparing bismuth nano wire array thermoelectric materials. The method is to take a high-purity BiCl3, glycerol and ammonia water solution as an electrodeposition solution, adopt electrochemical technology and utilize cyclic voltammetry to perform electrodeposition on an alumina template, and finally obtain the one-dimensional orderly Bi nano wire array thermoelectric materials with high thermoelectric conversion efficiency. The invention has simple preparation method and high filling rate; the maximum characteristic of the materials is that the materials can receive various forms of heat energy (including various types of radiant heat, solar energy, body temperature, heat generated in the system operation process, various types of waste heat and the like) from the environment and highly efficiently and directly convert the heat energy into electric energy which is then outputted; and due to the characteristics of the special high-density nano wirearray structure, oxidation resistance, high temperature resistance, high field emission current density, low turn-on field, good emission stability and the like, the application of the materials to field emission microelectronic devices as cathode materials can be realized and the materials have wide commercial application prospect.

A method for preparing a rhenium-impregnated scandium-tungsten-based alloy cathode, the preparation method comprising: mixing metal scandium powder and tungsten powder to obtain evenly mixed scandium-tungsten alloy powder; mixing the scandium-tungsten alloy powder with (1.5-3)wt % nitrocellulose solution is evenly mixed, and the mixed solution is applied to the surface of the tungsten wire cathode substrate, and baked; the tungsten wire with scandium-tungsten alloy powder applied on the surface is placed in a high-temperature hydrogen furnace, and kept at 1350±50°C for 5-10 Minutes, the scandium-tungsten-based alloy layer is prepared; then, the surface of the scandium-tungsten-based alloy layer is impregnated with a mixture of metal rhenium powder and (1.5-3) wt% nitrocellulose solution, and then baked; the surface of the scandium-tungsten-based alloy layer is impregnated Put the tungsten wire with metal rhenium powder into a high-temperature hydrogen furnace, and keep it warm at 1500±50° C. for 5 to 10 minutes to prepare a rhenium-impregnated scandium-tungsten-based alloy cathode. The rhenium-impregnated scandium-tungsten-based alloy cathode prepared by the method of the present invention can increase the emission current density of the pure tungsten wire cathode for a magnetron, reduce the working temperature and surface evaporation rate of the pure tungsten wire cathode, thereby prolonging the life of the cathode and the magnetron .

A method for preparing a direct-heating high-temperature tungsten-rhenium alloy cathode, the method steps comprising: mixing metal tungsten powder and rhenium powder to obtain evenly mixed tungsten-rhenium alloy powder; mixing the tungsten-rhenium alloy powder with 1.5-3 wt% nitric acid Mix the cotton solution evenly, apply the mixed solution on the surface of the tungsten wire cathode substrate, and bake; put the tungsten wire coated with tungsten-rhenium alloy powder on the surface into a high-temperature hydrogen furnace, and keep it warm at 1500±50°C for 5 to 10 minutes. The tungsten-rhenium alloy layer is prepared; then, the tungsten wire with the tungsten-rhenium alloy layer sintered on the surface is placed in an air pressure of 10 ‑3 ~10 ‑1 In the benzene atmosphere of Pa, the high-temperature chemical reaction is carried out at the temperature of the tungsten wire at 2000-2400K, and the reaction time is 0.5-2 minutes, and the direct-heating high-temperature tungsten-rhenium alloy cathode is prepared. The direct-heating high-temperature tungsten-rhenium alloy cathode of the invention can increase the emission current density of the pure tungsten wire cathode for a magnetron, reduce the working temperature and surface evaporation rate of the pure tungsten wire cathode, thereby prolonging the life of the cathode and the magnetron.

A method for preparing a direct-heating electron bombardment-resistant cathode, the method comprising: metal tungsten powder and Y 2 o 3 -Gd 2 o 3 -HfO 2 / ZrO 2 (Y-Gd-Hf / Zr-O) active substance powders are mixed to obtain uniformly mixed Y-Gd-Hf / Zr-O active substance powders; Mix the cotton solution evenly, apply the mixed solution on the surface of the tungsten wire cathode substrate, and bake it; put the tungsten wire coated with active substance powder on the surface into a high-temperature hydrogen furnace, and keep it warm at 1500±50°C for 3 to 10 minutes. A directly heated cathode resistant to electron bombardment was prepared. The direct-heating electron bombardment-resistant cathode of the present invention has better resistance to electron bombardment, and the cathode can increase the emission current density of the pure tungsten wire cathode for a magnetron, reduce the working temperature and surface evaporation rate of the pure tungsten wire cathode, Thereby prolonging the life of the cathode and the magnetron.

The invention provides a multi-channel foldable box type low-altitude sounding rocket launching device which comprises a box body, an orientator assembly, a supporting rod and supporting legs. The orientator assembly is connected with the box body through a support lug shaft; one end of the supporting rod is connected with a supporting lug at the bottom of the box body, the other end of the supporting rod is connected with a supporting lug on the orientator assembly, the length of the supporting rod is adjustable, and the launching angle of the orientator assembly is adjusted by adjusting thelength of the supporting rod. The four supporting legs are connected to the box body through the supporting leg shafts, the supporting legs can rotate around the supporting leg shafts, the supportingarea formed by the four supporting legs is adjusted by changing the rotation angles, and therefore the launching stability is improved.

The invention belongs to the field of vacuum electronic devices, in particular to a compact low magnetic compression ratio magnetron injection electron gun. Based on the electron gun design theory, the present invention improves the cathode structure of the traditional magnetron injection electron gun. The improvement points are as follows: the post-forming pole is composed of a cylindrical part and a circular truncated part, and the bus bar of the circular truncated post-forming pole is the first circle. Arc-shaped curve; the launch belt is in the shape of a truncated cone, and the busbar of the truncated cone of the launch belt is a second arc-shaped curve; the front forming pole is cylindrical, and the connection between the busbar of the front forming pole cylinder and the transition section of the front forming pole is A smooth curve that is concave inward. Through the above improvements, the miniaturization of the low-frequency magnetron injection electron gun is realized, and the cathode electric field adjustment capability of the electron gun is further improved, so that the electron gun has better overall performance. Compared with the traditional design method, the electron gun of the present invention is smaller in size, and can be used for vehicle-mounted radar or electronic countermeasure system mobile platform.

The invention provides a cathode of a cold-cathode X-ray tube. The cathode of the cold-cathode X-ray tube comprises a cathode base and a grid electrode, wherein the cathode base is composed of an upper cylinder and a lower cylinder which are coaxially arranged, the section of the cathode base is in an inverted-T shape, a cathode bar through hole is formed in the central axis of the cathode base, a cathode bar is arranged in the through hole, the three-dimensional size of the cathode bar can be controlled, an electron emitter is arranged on a cathode head, the grid electrode is of an cup-shaped structure, an inverted-T-shaped groove which is matched with the cathode base is formed inside the grid electrode, the cathode base can be embedded in the groove of the grid electrode and does not make contact with the inner wall of the grid electrode, and a semi-conical electron transmission hole used for focusing electrons emitted by the cathode is formed in the center of the grid electrode. According to the cathode of the cold-cathode X-ray tube, the cold cathode made of carbon nanomaterials is used as the X-ray tube of an electron emission source, and preparation of the cathode and the emission area can be effectively controlled through the size of the cathode bar; the three-pole structure is adopted, a small focus point can be obtained through focusing of the grid electrode, and the resolution ratio of X-ray imaging is increased.

The invention discloses a lanthanum-carbide-tungsten hot cathode material and a preparation method thereof, belonging to the technical field of cathode materials of refractory metals. The lanthanum-carbide-tungsten hot cathode material is characterized by containing La2C3 and metallic tungsten powder, wherein the content of lanthanum carbide accounts for 5%-20% of the total weight of the material. The preparation method comprises the following steps of: mixing lanthanum hydride powder and graphite powder with the mass ratio of 8: 1 uniformly under protection of argon atmosphere, putting the mixture in a vacuum furnace, heating to 1200 DEG C, preserving the heat for 30 minutes and obtaining a product La2C3; mixing the prepared La2C3 and the tungsten powder uniformly in vacuum by using a ball milling method, then putting the powder in a grinding tool and using ion sintering methods such as discharging and the like to carry out sintering; and adopting a locomotive processing method to prepare the needed cathode. In the lanthanum-carbide-tungsten hot cathode material, the preparation process is simple, the heat emission performance is good and the emission stability is good.

Suggested is a semiconductor nano-sized light emitting material having a ligand.

A method for improving performance of carbon nanotube film electronic field emission by electrophoresis deposit means includes plating transition metal film on conductive substrate material by physical gas phase depositing process, utilizing plated conductive substrate as cathode to deposit carbon nanotube film on said cathode through electrophoresis depositing process and carrying out annealing treatment on cathode deposited with carbon nanotube film for raising field emission current density.