In the process of removing tiny metal burrs in the vacuum tube, DC high voltage dedurring has some problems such as removing burr, removing unclean, larger burr residual, and influencing the test of product voltage and frequency. In order to overcome the technical shortcomings of DC high-voltage deburring, high voltage pulse with low repetition rate is used to remove the burr. In order to overcome the complicated design and high cost of the traditional high -voltage pulse power supply with vacuum tube as pulse switch and the whole circuit and control loop of all solid-state high-voltage pulse power supply with semiconductor device as pulse switch, a high voltage low frequency and wide duty ratio based on two transistor forward converter pulse for deburring power supply is developed. Through increasing the number of two transistor forward converters, and dual forward converter, it can meet the wide duty cycle of high voltage output. The design of the main circuit and control loop of the power supply is simple, stable, reliable, expansibility and low cost, which provides a relatively new solution for the design of high -voltage pulse power supply. The experimental results show that the output parameters of the power supply meet the design requirements, and are stable and reliable.

Arc ion plating is one of the most commonly used technique in vacuum film depsition technology, a long -term development in the fields of scientific research and industrial production have been obtained in present. However, the effects of some process parameters including arc current, deposition pressure, deposition temperature, etc. on film structure and properties were often scattered in different literatures during film deposition, being not conducive to the deep understanding of these parameters. This present paper reviews the role of the process parameters including arc current, deposition pressure, target - substrate distance, substrate bias, deposition temperature and external magnetic field, etc. It can be deeply recognized for the roles of these parameters on film structure and properties, through the summary of these process parameters during film deposition, which promotes the process development and progress of vacuum film deposition technology.

The development status of vacuum arc skull investment casting equipment at home and abroad is described. The application of this kind of equipment and the technical characteristics of equipment development companies in various countries are briefly compared and analyzed. Focusing on the electrical parameter design of the core components of the vacuum arc skull casting equipment, the current density characteristics of different conductive structures are summarized and the special phenomena such as the uneven conduction and distribution of the vacuum arc around the electrode rod and molten pool are discussed and analyzed. Finally, several directions of the development of precision casting technology are introduced.

As a type of field emission cathode material, carbon nanotube film shows various of benefits, such as no thermal effect, physico-chemical stability and fast-response, which make it suitable for kinds of vacuum electronics devices. This paper reviews the researches on preparations and applications of carbon nanotubes in Lanzhou Institute of Physics. The experimental method for preparing carbon nanotube films with different micromorphologies by chemical vapor deposition method is summarized. The field emission characteristics of different carbon nanotube cathodes were analyzed. The recent applications of carbon nanotube cathodes in the ultrahigh vacuum measurement instruments and ion thrusters are also introduced.

In this paper, we successfully developed a test method based on the L300 series helium mass spectrometry of LEYBOLD to test the total leakage rate of spacecraft used to a non-vacuum accumulative helium detection method. After many tests, the results show that the as-developed spacecraft total leakage rate test system has high measurement accuracy and stable performance. It not only reduces the total leakage rate of the spacecraft system to a minimum, but also reduces the weight of the equipment and increases the mobility. It has some engineering applications and popularization values.

The similarity law of the liquid ring compressor performance is the main basis for developing products and expanding their operating ranges. Currently, the study of the similarity law of liquid ring compressor at home and abroad is quite different. The structure, working principle, medium and flow law of liquid ring compressors are very different from those of vane pumps and compressors. The current similar laws cannot be directly used for liquid ring compressor. In this paper, the 2BE1 liquid ring compressors were selected as the research object. The external performance test and statistical regression method were performed. MATLAB fitting function polyfit was used to fit the test data regression. The similar relationships were obtained between the performance parameters such as the suction flowrate and shaft power with the parameters such as the rotational speed and the geometric ratio of the liquid ring compressor, which could provide the basis for the optimum design and application of the liquid ring compressor.

The Al -doped ZnO (AZO) thin films were deposited by DC -RF coupled magnetron sputtering system on glass substrates at room temperature. The RF sputtering power increased from 0 to 200W. The structure, surface morphology, optical and electrical properties of the AZO films were investigated by using X -ray diffractometer, scanning electronic microscope, ultraviolet-visible spectrophotometer and hall effect test system as a function of different RF sputtering power, respectively. The results indicate that AZO thin films with excellent performance can be prepared by DC-RF coupled magnetron sputtering at room temperature. Meanwhile, the RF sputtering power has a significant impact on the optical and electrical properties of the AZO thin films. With the increase of RF sputtering power, the compactness of AZO films and the grains size were increased, the surface morphology and growth form of the AZO films change greatly. Under RF sputtering power of 200W, the lowest resistivity of the AZO film is  5.39×10 ^-4 Ω·cm. The average optical transmittance of the AZO film prepared at room temperature is approximately 82.6% in the visible wavelength.

The cleaning sources with argon ions using vacuum arc discharge technology are new methods to improve the adhesive strength between top layer and substrate, where electrons coming from arc discharge plasma by hollow cathode gun, heater filament gun and vacuum cathode arc sources produce argon ions and then the argon ions were used to clean the samples before coating process. With the help of this technology, bias currents on substrate holder can reach between 10A and 30A under the condition of bias voltages of only 200V. This new clean method has great advantage, since it brings the high ion density. The article also gives a brief introduction on the vacuum arc deposition systems and magnetron sputtering system with this advanced Ar ⁺ cleaning sources.

In this article, the selection of thin film materials, failure mechanism, mechanical properties test method and fatigue failure are reviewed. The influence of tensile bending on the microstructure of the film and the initiation, electrical properties, expansion and saturation of microcracks were analyzed. The effects of film material, grain size and film thickness on the fatigue life of thin film were summarized. On membrane surface, along the thickness direction and control of fatigue crack was discussed. It is shown that the future studies on mathematical modeling and film fatigue experiment need to be combined together for better results.

With the rapid development of superconducting technology, more and more attention has been paid to the refrigeration system that provides cryogenic environment for superconducting materials. This paper introduces a sub -cooled nitrogen cooling system for HTS motor based on the principle of decompression and cooling. It includes the technical specifications and related requirements, the overall structure, key technologies, thermal load analysis and calculation, etc. The system adopts vacuum cooling to obtain sub-cooled liquid nitrogen and coil wires in the cooling motors. Liquid nitrogen inlet and outlet temperatures are 68K and 72K, respectively. The utility model is mainly composed of a liquid supply dewar, a sub-cooled box, an evacuation pump, a superconducting coil dewar, a reflux dewar, a low temperature pipeline and a temperature meter. The experiment indicates that the cooling system is reasonable in design and easy to operate, and the loading operation of the superconducting motor is successfully realized.

Carbon nanotube(CNT) field emission cathode has the advantages of quick start, high resolution, long lifetime, and low power consumption. The CNT cathode can be employed in a variety of vacuum electronic devices and components, including flat panel display, vacuum measurement, and vacuum electronic devices. This article discusses major methods for development of carbon nanotube cathode, and emphasizes on direct growth of CNT emitters on catalytic substrate by chemical vapor deposition and substrate anodization with strong adhesion and advantages for applications in the X -ray tube and other vacuum electronic devices. The field emission properties of CNT cathode grown directly on stainless steel substrate are investigated, with the turn -on electric field of 1.46 V/滋m. The high current emission and stability properties of the direct grown CNT emitters are improved significantly comparing with that of the CNT cathode by conventional synthesis on catalytic metal film. The substrate anodization improves clearly the CNT structure and field emission performance. Advantages of large scale production of up to 2 cm in diameter and high current emission of 500 mA/cm2 are also demonstrated.

The anode layer ion source, with simple structure, high beam density and controllable ion energy, can be applied for surface modification especially in large area. It can be also applied for applications of ion beam assisted deposition, thin film etching and surface cleaning. This paper reviews the history and development of anode layer ion source. It introduces the principles of anode layer ion source and research status, discusses its key designs, including the design requirements of magnetic field, electromagnetic field and gas discharge simulation. Finally, it summarizes the applications and future developments of anode layer ion source.

Micro -nano structured Al -doped ZnO thin films were deposited by DC -RF coupled magnetron sputtering system binding winding bar scraping coating on glass substrates at room temperature. The RF sputtering power ratio of basement AZO film was adjusted from 50% to 90% . The structure, surface morphology, optical and electrical properties of the micro -nano structured AZO films were investigated by X-ray diffractometer, scanning electronic microscope, Hall effect test system, ultravioletvisible spectrophotometer and WGW, respectively. The results indicate that the resistivity of the micro-nano structured AZO film is dominated by RF sputtering power ratio of the basement AZO film. The films deposited under RF sputtering power ratio of 80% exhibit the lowest resistivity of  5.32×10^-4 Ω·cm. The average optical haze is approximately 36.3% in the visible wavelength. With the increase of RF sputtering power ratio, the surface morphology, growth form and the particle size of the films change greatly. Meanwhile, the micro-nano structured AZO films show light trapping effect and excellent optical and electrical properties.

With the development of carbon composite materials, the temperature of graphitization is getting higher and higher, while the external dimensions of the workpiece are getting bigger and larger. The requirements for the high temperature graphitization furnace are thus put forward. In this paper, the power calculation of large size graphitization furnace with a resistance heating cylindrical heat preservation structure is introduced including the technological characteristics, structure type and the selection of calculation parameters.

Radio frequency magnetron sputtering was used to deposit Mg doped Gallium oxide(Ga₂O₃) thin films with different Mg concentrations by alternate sputtering of Ga₂O₃ and MgO targets. The results showed that with the increase of Mg concentration, the crystallinity of the films decreased and the thickness of the films reduced; the light transmittance had no obvious change, but the band gap increased gradually, so we can change the band gap width of Ga2O3 film continuously by doping Mg into Ga2O3 film rangeing from 4.96 eV to 5.21eV; The PL spectroscopy results show that the doping of Mg leads to a blue shift of the PL peak, and a new luminescence peak appears near the 473 nm blue light.

The principle and characteristics, current application status and equipment of vacuum conveying technology were summarized in this article. The future development trend and prospect of vacuum conveying technology were also analyzed and discussed. It may be helpful for the development of vacuum industry.

The experimental principle, device, sample preparation, test procedures and data processing of volumetric adsorption isotherm are introduced in detail. It was proved that the adsorption performance of 5A molecular sieve for CO₂, N₂ and H₂ was better than that of the 13X molecular sieve at liquid nitrogen temperature and low pressure. On the basis of analyzing the adsorption isotherms of 5A and 13X molecular sieves to CO₂, N₂ and H₂ at liquid nitrogen temperature and low pressure, the characteristics of adsorption isotherms of 5A and 13X molecular sieves at LNG and LH₂ temperatures were analyzed. The adsorption isotherms of 5A and 13X molecular sieve obtained under test at liquid nitrogen temperature and low pressure can provide good reference data for engineering design.

This paper describes a single vacuum pump operating parameter monitoring system. The system consists of a main master chip STM32F103ZET6 microcontroller and corresponding monitoring sensors. The system's overall design, measurement principles and some key technologies are introduced. The hardware design, software programming, transmission test and other processes are elaborated in detail. The system can acquire and display the operating parameters of the pump, including temperature, pressure, rotating speed and so on. It can also communicate with the PC host computer. The as-designed system is compact in size, low in power consumption, high in reliability and strong in anti -jamming capability, which can effectively realize the real -time monitoring of vacuum pump operating parameters.

To satisfy the special infrared calibration test of large caliber spaceborne remote sensor in space environment, the radiation shielded door was developed. In this paper, functional characteristics and working environment of the radiation shielding door are considered. The material selection, low temperature realization, radiation shielding, solid lubrication and measurement control are analyzed. The successful development of the radiation shielded door has solved the problems of heat radiation interference between the remote sensor, the blackbody and the simulated space environment during the infrared calibration. Meanwhile, accuracy of the infrared calibration is improved. The radiation shielded door with the largest "ultra large radiant surface vacuum calibration blackbody" in our country successfully implemented special large-diameter spaceborne remote sensor infrared calibration test, which marked the large-diameter infrared radiation calibration techniques in our country has reached the world-class level.

The Cr/CrN multilayer films are prepared to improve the corrosion resistance of the samples by arc ion plating. By controlling the deposition time of each Cr and CrN sublayer, the effect of the different modulation ratio on the Cr and CrN multilayer films is investigated from the microstructure and corrosion behavior. The results show that the multilayer has a suppressed effect on the coarse columnar structure by inserting the Cr layers, leading to a compact structure with lower porosity. Potentiodynamic polarization curves and electrochemical impedance spectroscopy results show that the Cr/CrN multilayer films exhibit an obvious corrosion potential increment of about 100mV, while the corrosion current density decreases more than one order of magnitude compared with that of the single CrN layer.

The vacuum leak detection is an important technology to obtain high vacuum in the drift tube linear accelerator (DTL). The quadrupole mass spectrometer is an important tool for analyzing the components of the residual gas in the vacuum system, and can also be used as a means of leak detection. In this paper, the DTL1^# cavity was detected by two means of helium mass spectrometer leak detector and quadrupole mass spectrometer. When the coil of the 12^# drift tube was applied current, the pressure, leakage rate and residual gas composition of the cavity were all changed, and the spectral peak of water increased most significantly. So there's something wrong with 12^# drift tube. The cavity quickly obtained the high vacuum of 10^-6 Pa by proper treatment, which met the requirements of the linear accelerator for vacuum system.

Four refrigerator cooled cryopumps (DN1250 LN₂) were designed and manufactured by BISEE. The pumps were used in space environment simulation system to meet the demand of the high vacuum in thermal vacuum test. The design and test method for pumping speed, cool down time and crossover were introduced in this paper. A test system was built to test the main performance of the cryopumps. The experimental results show that the pumping speed for N₂ of the pump is up to 57000 L/s, the cool down time is about 330min, and the crossover is over than 3.0 ×10⁵Pa·L.

The principle and characteristics, current application status and equipment of vacuum conveying technology were summarized in this article. The future development trend and prospect of vacuum conveying technology were also analyzed and discussed. It may be helpful for the development of vacuum industry.

In view of the disadvantages of large size and low efficiency of traditional DC high voltage generators, this paper designed a 200kV DC high voltage generator with a continuously adjustable output power of 400W. The focus is on the power and control part of the DC high -voltage generator, in which the power part was chosen to use the high -frequency inverter technology and high-frequency transformer with voltage doubler rectifier. The DSP was used for the control part as the system control core. Simulation results and theoretical analysis confirm the correctness and feasibility of the system design scheme.

This article briefly describes the effects of low -orbit space environmental factors such as atomic oxygen, ultraviolet radiation, charged particle irradiation and thermal cycling on material properties. The synergistic effects of ultraviolet radiation, charged particle irradiation and temperature cycling on the interaction of atomic oxygen with materials are reviewed. It provides a reference for ground simulation experiments of material space environmental effects, and also provides a basis for the study of multi-factor synergistic effects of materials.

This paper focuses on the environmental pollution and management of domestic and international enviroment, based on the engineering experience of polymerization gas recovery and oil & gas recovery, the application characteristics of the water ring pump unit in these different processes was introduced for specific cases under different process conditions. A digital structure model of the water ring compressor was established. The paper investigated the structure parameters formula of water ring vacuum pump under different process parameters, the combination of different process conditions and the materials selection. The development direction of equipment is energy -saving and environment -friendly. It shows that the chemical gases vacuum - compression recovery system has great potential in energy saving and corrosion resistance depend on industry innovation and technological progress.

Computational fluid dynamics and theoretical fluid dynamics, experimental fluid dynamics together constitute the fluid mechanics research field. With the development of computer science and technology, and the progress of mathematical theory and numerical method, computational fluid dynamics (CFD) is gaining more and more attention by researchers and engineering technicians. The prediction accuracy of CFD theoretical model is widely recognized, and CFD has become a research tool for complex flow and heat transfer problems, and an important design tool used in engineering fields and teaching tool of thermal fluid mechanics. CFD method has applied in vacuum engineering as a research tool to investigate the working mechanism of vacuum equipment. Numerical study of inner flow behavior in a steam-jet vacuum pump was carried out, the simulation results was analyzed to reveal the effect on the pumping performance by CFD approach, which can be used to optimize the structure and improve performance of the steam-jet pump.

Carbon films were deposited on different substrates, such as silicon, high-speed steel and stainless steel, by magnetron sputtering. Keeping other parameters constant, the pulsed negative bias varying from 100 V to 400 V was applied to the substrate in order to investigate the change of micro-structure and performance of the carbon films. The results show that all the as-deposited carbon films are amorphous and hard with good surface quality. The hardness, thickness as well as deposition rate of the carbon films increase initially and then decrease with increasing pulsed bias, while the friction coefficient behaves oppositely. The optimized mechanical properties of the carbon films are obtained at the pulsed negative bias of 200 V.

This paper studied the cause and the improvement measures of common defects in Fe-Cr-Al alloy ingots smelted by 150kg VIM furnace. Through four experiments, the influence of pouring temperature, pouring time, the lining use times and whether the tundish used a filter are studied on the surface quality and the internal shrinkage. The results show that the surface quality of the ingot is better and there is no shrinkage cavity defect under the condition that the pouring temperature is 1640 ℃, the pouring time is 0.56 min, the lining is used less and the tundish uses the filter.

In this paper, Tb thin film was deposited on the surface of sintered NdFeB magnets by the method of vacuum multiarc ion plating, and then a vacuum heat treatment was applied in the samples. Tb was introduced from the surface into the interior of the magnets by grain boundary diffusion (GBD), and the magnetic performance and heat resistance of the magnets was studied at last. The results show that after grain boundary diffusion treatment, the metal Tb enters the grain boundary within a certain depth range from the surface of the NdFeB magnet, resulting in the increasing of intrinsic coercivity of the magnets by 9000-10000Oe, and great reduction of high temperature hirr of the magnets. The intrinsic coercivity and heat resistance of the magnets were significantly improved.

The wall current probe, as a probe for measuring the longitudinal size and intensity of the bunch, is widely used in the accelerator system. The accelerator vacuum system is an ultra-high vacuum system, and the alumina ceramics are resistant to high temperature with high insulation performance, low outgassing rate and high dielectric strength. Stainless steel is resistant to corrosion, can be baked and has low outgassing rate, which is a common and excellent material for ultra-high vacuum system. This paper introduces the brazing technology of ceramic and Kovar, the argon arc welding structure of Kovar and stainless steel and the helium mass spectrometer leak detection.

With the wide application of high -power magnetron, people are paying much attention to the heat -dissipation performance of high -power magnetron, because the heat -dissipation performance of magnetron directly affects the lifespan and stability of magnetron. Referring to the working characteristics of air -cooled magnetron, we optimize the existing magnetron technology in this paper. Firstly we decide the designing direction of analysis and optimization theoretically, and then simulate it by the software Icepak, and obtain a feasible plan. Samples are made to test the actual heat -dissipation performance. We find that increasing the superficial area of the heat -dissipation system of the magnetron and improving the Reynolds number of the heat-dissipation system could obviously improve the heat- dissipation performance.

Ion getter pumps (IGPs) are particularly appropriate for use in modern accelerator facilities because of their high reliability, cleanliness and the absence of vibration that could disturb the trajectory of the beam. Normally, T-pieces are used to connect the pumps to the beam tube. These reduce the effective pumping speed and require the use of radiofrequency (RF) shielding which is complicated and expensive. Moreover, very often the accelerated particles are sensitive to stray magnetic fields and the impedance of the surrounding vacuum tube. Magnetic fields generated by the ion pump magnets, which are asymmetrically oriented to the beam tube, can be a major drawback. To overcome these problems, we have developed, in collaboration with the Deutsche Elektronen -Synchrotron (DESY), an innovative in -line ion getter pump which can be mounted directly into a beam line without a T -piece and which has a symmetrical arrangement of the magnets around the beam tube. Additionally, RF shielding can be easily integrated inside the in-line pump. Using this innovative in-line concept (Patent EP2 431996A1) ion pumps will become an integral part of the beam tube for the first time when installed on the X -FEL system at DESY. The arrangement of the magnets and the geometry of the pole piece, used to guide the magnetic field lines, were designed to minimize any disturbance on the beam trajectory. Moreover, the element location inside the pump has been optimized to“selfshield”the beam, without requiring the addition of expensive and complex optical shields. Finally, thanks to the in-line solution, a simple RF shield (a copper coated tube with pumping slits) can now be easily installed directly inside the pump at the accelerator site installed directly inside the pump at the accelerator site.

Numeric simulation of the three-layer hot-wall metal-organic chemical vapor deposition（MOCVD）vacuum reactor was performed, including the design and the final flow field distribution. In this article, on the basis of the optimization array of the nozzles, the substrates susceptor, the near ceiling wall around the susceptor and the wall above the susceptor were all heated and the partial hot-wall reactor was formed. Furthermore, the design of the vacuum reactor, the flowing speed of the top layer and the bottom layer were all investigated in detail. As a result, we can ensure that in the material growth region, the precursors and the carrier gases were all kept in a stable flow states without swirls and the precursors were concentrated on the position of the substrates, which increased the utilization of the reactive materials effectively and the reaction on the other wall was reduced largely. At last, materials was grown in this hot-wall MOCVD reactor and the thickness of the film was averaged. The FWHM of XRD rocking curves for the wafer is 149.8 arcsecond, indicating that good materials quality was gained.

The vacuum pumping technologies are discussed and it will give years of reliable service when properly applied and operated. However, when troubleshooting is required, the fault diagnosing and applying correct solution can be equally as important.

Spacce traveling-wave tube (STWT) are used in a wide variety of areas, such as radar, space technology and electron accelerators. The vacuum is one of the basic conditions for the work of STWT. We use ultra -high vacuum exhaust station to obtain a microwave device with the ultimate vacuum better than 5 伊 10 -9Pa; The residual gases in a macro-wave device during thermal degassing was in-situ monitored with quadrupole mass spectrometer ( QMS ). The major residual gases, including but not limited to H2O, CO, and H2, was investigated. It is shown that 36 hours was economically for the baking exhaust time. The operating principle and method of vacuum leak detection using QMS are introduced, and the leak detection was conducted for macro-wave device experimentally. Satisfactory results were obtained and showed that QMS has so predominant advantage that no leak detector can get over. A test platform for measuring the vacuum of the microwave device has been established. After the STWT sealing off the exhaust equipment, sophisticated, storage and high and low temperature test process of vacuum was tested. When the STWT is sophisticated, the vacuum in the device is reduced by an order of magnitude. After 140h, the vacuum of the device rises to 5.0 伊 10-8 Pa under the ion pump. At this time, the vacuum remained basically unchanged after removing the ion pump. Finally, high and low temperature impact experiments were performed and stored at room temperature for 6 months, the vacuum of the STWT is kept in good. These results provide a good basis for analyzing the quality of the STWT.

The MoS₂ nano-precursor solution was synthesized by sodium molybdate and thiourea. The nano-powder was obtained by vacuum freeze-drying method under different freezing modes. The morphology and particle size of the nano-powder materials were studied by transmission electron microscope and atomic force microscopy instruments. The results show that the nanometer molybdenum disulfide prepared by vacuum freeze -drying method has a particle size of 25nm -37nm. At the same time, the nanometer molybdenum disulfide was added as an additive to the paraffin oil. The friction performance was measured by a fourball friction tester. The size and friction coefficient of the wear spot were both significantly reduced.

The low-temperature adsorption bed is an crucial part for the pressure recovery system of the chemical laser. In order to reduce the weight of its shell, this paper uses the finite element analysis method to explore the design method and optimization scheme to make adsorption bed shell and lid with low-temperature aluminum alloy material instead of stainless steel. The results show that the strength and vacuum condition of the aluminum alloy material adsorption bed have both met the design specifications, opening a new approach to design the low-temperature adsorption bed for the use of lightweight material.

A small-scale vacuum evaporation system specialized for organic light-emitting diodes (OLED) research was designed based on the advantages of worldwide OLED fabrication systems. The mask cassette, evaporation chamber, transition chamber and glove box were arranged in line. Organic thin films and electrodes for OLED devices with different structures can be deposited in-situ in the system, which satisfies the requirements of ultra-low water and oxygen content for device packaging. The system structure, core components and pumping system were analyzed and calculated.

Photo-stimulated-desorption is the synchrotron radiation beam line, which is different from the typical vacuum system. In the whole process of the Photo-stimulated-desorption, photoelectron and secondary electron play a major role in the excitation of adsorption gas on the surface of vacuum material.Theelectron-stimulating desorption equipment (ESD) is important in studying the electron-stimulating gaseswith different materials and processes. Through theoretical calculation and analysis based on the physical process of electron-stimulating desorption, this paper has developed an equipment for above-mentioned experiments in 400eV~1000eV electron energy, which provides the experimental basis for studying optimal processing and treatment process of material surface in vacuum.

In this paper, the external surface condensation and partial icing problems of some vacuum multilayer insulation pipes in a launching site are analyzed in detail. Improving measures are then put forward, which may provide reference for future production of vacuum insulated pipes.

One of the key tasks of China's lunar exploration phase three project is to collect lunar sample and return to earth under the condition of unmanned state, and to maintain the original state of the lunar sample, and to ensure the accuracy of the ground data analysis. Aiming at the characteristics of the mission for the lunar sampling in China, and by referring to the successful experience abroad, this paper designs a sealing structure and locking mechanism to automatically seal the lunar sample. The design can realize the vacuum seal with extremely low leakage rate of the lunar sample, and can still maintain the leakage rate of the sample container after withstanding some mechanical environment conditions. The ground test verification indicate that the design can meet the expected target and the needs of lunar sampling mission in China.

The liquid helium cryogenic system(LHCS) is an auxiliary facility of HL-2M tokamak, which is being built in Southwestern Institute of Physics(SWIP), the demand of liquid helium from cryogenic users are 16m³ per week. So it's necessary to construct a helium recovery and purification system (HRPS), which consists of a recovery part, a storage part and a purification part. The recovery part mainly includes 2 piston compressors with capacity 50m³/h and 100m³/h respectively; the storage part mainly includes 4800m³ higher purity helium tanks, 1200m³ dirty helium tanks and 50m³ two gasbags; the purification system mainly includes a high pressure helium purification equipment, which can improve the helium purity from 95% to 99.999% or even more. The maximum recovery rate of the system is designed to 150m³/h.

In the development process of the microwave tubes, the main purpose of vacuum degassing system for the electron gun is to obtain the data between current/voltage and temperature, to test the quick start parameter, to measure thermal expansion and to minimize the material evapotranspiration and outgassing. According to the relation between structure and property of the electron gun, two operating station vacuum degassing system was designed and developed with the function of temperature, thermal expansion and other measure property. The final system pressure is better than  2×10^-7 Pa. In the vacuum degassing system, mechanical pump is used as the backing up pump, while the molecular pump and the ion pump are the main pumps. Each operating station can work simultaneously to improve the quality and to save time for increasing the efficiency. Indicator lights are equiped with the system to prevent the potential problems for the electron guns or the vacuum system that is caused by misoperation. A large amount of data obtained from experiments verifies the working principal, structure design and good properties of the system. It is applicable to different types of electron guns for microwave tubes, which has important significance in the small amount production of klystrons.

Based on the development of the high temperature working infrared detector Dewar module, the conduction heat load and radiation heat load, which influences the Dewar heat load index importantly, are analyzed and the improved method of Dewar design is proposed. The conventional method of Dewar leak test and the defects of Dewar heat load test under high operating temperature are analyzed. The vacuum protection calorimetry method is adopted to realize a reliable method for heat load detection of high working temperature type Dewar components, which can promote the development of three generations of infrared focal plane detector components.

The acceleration power supply is an important part of high energy ion implantation system and provides energy for ion acceleration. According to the parameter requirements of new type high energy ion implantation system with adjustable voltage from 10kV to 100kV and the ion beam current strength less than 20mA, an acceleration power supply was designed based on DSP to improve the traditional acceleration power supply structure. This paper discussed the main circuit structure of the power supply including three-phase rectifier, buck chopper voltage regulation, full bridge inverter, transformer booster, voltage doubling rectifying circuit and it's simulation analysis.

The cleaning method of steel tube in the pretreatment of coating was studied. The steel tube was cleaned by multiple ultrasonic cleaning modes, then dried naturally, cured at high temperature, and the pretreatment quality of the steel tube coating was analyzed. The test results show that the stainless steel pipe after precision polishing adopts the solvent ultrasonic cleaning + tap water ultrasonic cleaning + deionized water ultrasonic cleaning + deionized water washing + drying process is feasible and can meet the requirements of the subsequent coating process for future realization. The production automation process operation improves the test basis.

The pressure within capsule need to be regulated and controlled by the pressure control system outside the vessel in the process of thermal vacuum test for spacecraft with capsule. Generally, the capsule is connected with the pressure control system via pressure -controlled pipeline (metal bellows). Any leak in the joint of the pressure -controlled pipeline and capsule would make the thermal vacuum test for spacecraft impossible, hence it is of great importance to ensure that the leak rate of joint meet the test requirements. This thesis, studying the specific structure of joint, achieves the leak detection method of the joint, which is verified by test and acquires good effect.

Due to memristor's unique electrical characteristics, it has a good prospect in resistive random access memory, artificial neural networks and circuits. The cross -bar was widely used in two -dimensional integration, the three -dimensional integration can be divided into stacked cross -bar array and vertical cross -bar array. The two kinds of three -dimensional structures, models under different mechanisms, window functions and circuit structure were compared and discussed, the method of improving the integration density was analyzed. The memristor's biological synaptic behaviors, application in artificial neural networks and circuits were also introduced.

In this paper, the optical reflector was chosen as the research object. The customer requirements on the optical reflector film quality and the quality flaw producted in production process were obtained by QFD. Combined with the optical mirror coating process, the demand in the form of quality house was transformed to process factors that affect the film surface defects of plating process for thin films. The design of key process factors and test process were optimization by using DOE test method. The results were analyzed by means of test and the range analysis method. The optimal combination of process parameters was thus obtained to prevent film surface defects. The experimental results show that the integrated improved model of QFD and DOE can achieve good practical application effect in the surface performance of reflector film.