As a flexible material with similar structure to biological tissue, hydrogel has been widely used in flexible sensors and other fields. However, the mechanical properties of hydrogel are poor because of its high water content, and the hydrogel is easy to freeze and fail under low temperature environment. This paper reviews recent studies of hydrogel from the aspects of toughening mechanism, antifreeze method, and fatigue characteristics. Firstly, the mechanical properties and internal structures between different toughening hydrogels are compared. Secondly, the antifreeze method of hydrogel under low temperature is discussed. Finally, the fatigue damage characteristics of hydrogel in long-term static or cycle mechanical loading are summarized. In the future, it should be committed to increase the water-freeze resistance of hydrogel, and further study the hydrogel fatigue failure mechanism, which may provide theoretical basis for the application of low temperature and fatigue resistant hydrogel sensors.

In order to make better use of the properties of active spectrum control of electrochromic glass and provide theoretical support for the application of electrochromic glass in architecture, the sealed insulating glass unit was taken as an example to discuss the changes of visible light transmittance and shielding coefficient(energy saving effect). It is found that in order to obtain a larger visible light transmittance difference(bleach state minus color state), the key point is to improve the transmittance of electrochromic glass. However, compared with the electrochromic glass with higher cost, it is more realistic to improve the transmittance of Low-E glass.In order to give full play to the energy-saving characteristics of electrochromic glass, the electrochromic glass was placed on the outdoor side and indoor side of insulating glass respectively for testing. The results show that when the electrochromic glass is located on the outdoor side, the change of shielding coefficient is the largest(0.46), which is more suitable for a variety of scenarios. At the same time, the better performance of electrochromic glass film is required.

Time of flight second ion mass spectrometry(TOF-SIMS) and pulsed radio frequency glow discharge optical emission spectrometry(Pulsed-RF-GDOES) are two important depth profiling techniques, the former one is widely used in the fields of semiconductor industry and material science, while the latter one is usually applied to the analysis of industrial coating and surface oxynitride. Mo/Si nano-multilayers have been widely used in nanolithography, soft X-ray/EUV microscopy, solar astronomy and other fields because of their excellent reflection characteristics. In this paper, Pulsed-RF-GDOES and TOF-SIMS depth profiling data of Mo(3.5nm)/Si(3.5nm) nano-multilayer are evaluated quantitatively by the convolution and deconvolution methods with the resolution function of the atomic mixing-roughness-information depth(MRI). The layer structure, interface roughness and depth resolution upon depth profiling are obtained. The results show that GDOES depth profiling yields larger sputtering induced roughness, and the depth resolution of SIMS is better than that of GDOES.

The ultra high vapor and oxygen barrier film, which can protect the organic electronic device from water vapor erosion and prolong lifetime, is widely used in flexible electronics, such as organic thin film solar cells, OLED displays, quantum dot displays and other electronic packaging. According to the research status of the preparation technology of high barrier film, in order to improve the performance and meet the demand of rapid development of flexible electronic packaging, the effect of substrate material is analyzed, the multilayer preparation technology is summarized. Finally, the future development trend of barrier film technology is prospected.

The preparation method of protective and passive film for Cu electrode of enhanced power device is introduced. Al₂O₃ films are deposited on copper by thermal ALD and plasma enhanced ALD techniques. The effects of different ALD techniques, oxidant type, deposition temperature and carrier gas on the quality of Al₂O₃ films and the protection performance for Cu oxidization are studied. The results show that oxidants play an important role in Al₂O₃ film quality and the protection performance for copper electrode. When ozone(O₃) is used as oxidant, Al₂O₃ film deposited on copper layer is easy to fall off, and the adhesion to copper surface is very poor. Using oxygen plasma (O-) as oxidant, copper surface is oxidized to form CuO_x layer. With H₂O as oxidant, the Al₂O₃ film obtained at low temperature of 100℃ is dense without obvious defects, and has excellent bonding force with copper layer. When the deposition temperature is higher than 200℃, the defects of Al₂O₃ deposited by ALD increase obviously. In plasma enhanced atomic layer deposition, when the carrier gas is Ar, the thickness of Al₂O₃ film is not uniform, and the copper electrode is strongly oxidized.

Study of the rotor profile of Roots pump is a core part of Roots pump design, and the circular arc rotor profile is one of the widely used for Roots pump. In the design of circular rotor profile, the theoretical rotor profile is designed based on conjugate properties firstly. Then the actual profile and casting blank profile of the rotor are obtained based on the theoretical profile. In this paper, the actual profile and casting blank profile design method based on the rotor circular arc line is proposed on conjugate properties to greatly simplify the analysis and design process. Finally, the circular arc rotor profile and its rough machining and finishing methods are designed for a 70L/s Roots pump.

A system is designed to test the gettering performance of gas adsorption materials by using the principle of dynamic method, which can achieve high vacuum(5.0×10^-4Pa) to several atmospheres in the temperature range of 15-500K, measure the instantaneous adsorbing speed, adsorption capacity and saturation gas capacity of various materials for different gases accurately. The test results show that the system has the characteristics of high background vacuum, reasonable and compact structure, and accurate and reliable test data.

Based on space TWT environmental simulation and test process feedback using thermal vacuum test device, meanwhile, adapting to the small volume production, an innovative and optimized design of the thermal vacuum test device for space TWTs was carried out. According to the technical indicators, the cold plate structure and heat sink heating method are optimized, the vacuum system configuration and installation method are changed, and some manual operations are changed to automatic operations. The temperature uniformity is improved, and the whole process can be operated one-touch operation in intelligent control after optimization. It also improved the operating environment and makes the operating space more humanized.For the abnormal vacuum degree and component failure in setting up the new process, the diagnosis and treatment are carried out by step detection, item by item investigation and superposition.

The paper introduces the necessity and working principle of the leakage monitoring equipment,and its detailed structural design, mainly including the evacuating device and the gas component analysis device of co-bulkhead tank, the evacuating pipe and the optimization of the equipment work process in launch site. At present, the two sets of equipment developed have been successfully delivered to launch site, and have participated in three space launch missions. The use of the equipment effectively ensured the safety of spacecraft and test personnel during the rocket launch mission. In the future, the equipment will continue to serve the high-density launch mission of the new generation medium carrier rocket.

As a dry medium and low vacuum pump, screw vacuum pump has many advantages such as wide pumping speed range, low energy consumption, no oil pollution, etc., and is widely used in various fields. In order to serve the national carbon neutral development strategy, this paper applies the accounting and management method of carbon footprint to the design and manufacture of screw vacuum pumps. By tracking, analyzing, accounting and managing the carbon footprint of the entire product life cycle, specific measures to reduce carbon emissions are put forward from the perspective of design, processing and manufacturing, supply chain transportation and institutional levels. The research of this work will help enterprises to formulate relevant carbon neutral goals, complete the accounting of carbon footprint, and achieve the purpose of energy saving and emission reduction.

Due to the advantages of clean and environmentally friendly,abundant raw material reserves,safety and reliability,and no nuclear waste,sustainable green energy nuclear fusion has become an important choice to solve energy and environmental problems in future.However,achieving controlled nuclear fusion is not easy.Tokamak is the most promising magnetic confinement device to realize controllable fusion energy.High power vacuum launch tube is an important component in the Tokamak device.As an important index of the limit parameter and rated power of the transmitting tube,its current depends on the structure,size,material of the transmitting tube itself.The structure and working principle of the tetrode are very complex,so it is very difficult to obtain the variation of emission current with its structural parameters.Therefore,the tetrode can be equivalent to diode structure to explore the law of space charge limited current of diode changing with its geometric structure.The results can provide reference and theoretical basis for the structure design and optimization of the plasma heating transmitting tube.At present,there are many analyzing methods and special simulation software,and they have been widely used in the space charge limiting current.In this regard,by reviewing the related literature and books,the research status of the space charge limited current of the diode at domestic and overseas are summarized and analyzed,and the development tendency is prospected.

Scanning ion gun is a common component for sample surface cleaning,surface etching and deep analysis, the acceleration voltage of which can be adjusted from 500V to 3kV. It has the advantages of high efficiency and reliable performance. Electron optical system is an important part of ion gun and an important parameter to determine the ion beam quality. In this paper, the computer simulation software CST is used to model the overall structure of the ion gun, the effects of different structure and voltage parameters of the ion gun focusing system on the ion beam current density and beam spot size are studied, and the ion distribution of ion gun deflection system under different voltage distribution is obtained. The design scheme of the electronic optical system is determined by simulation analysis and is verified by experiments. The test results show that when the working distance is 25mm, the working pressure of argon gas is 6×10^-3Pa and the acceleration voltage is 3kV, the argon ion beam size is 3μA. Beam spot size can be adjustable from 7mm to 12mm. The deflection angle is 4.6° when deflection voltage is 300V. The test results are basically consistent with the simulation results, and the surface atomic precision structure can be achieved by the performance index of the ion gun.

The external pipelines of aero-engine usually work in vibration condition, which is prone to cause vibration fatigue damage and failure. According to the vibration fatigue life estimation method theory, the vibration fatigue life estimation methods of aero-engine external pipelines in time domain and frequency domain are analyzed. The applicable characteristics of time domain method and frequency domain method for life estimation of aero-engine external pipelines are given. This paper can provide a theoretical basis of vibration fatigue life estimation for aero-engine external pipelines.

At present, some high-performance NdFeB magnetic material needs to be stored in a glove box filled with inert gas before sintering. However, in terms of operation mode, each furnace still works independently, and there is no information exchange between furnaces. The charging mode is that the on-site operator manually moves the glove box to connect with the furnace to complete the feeding and discharging of the furnace, and then according to the furnace production process, the operator performs the vacuuming, heating and cooling manually. With the intelligent transformation of production equipment, reliability, economy and practicability have always been the goals of the production workshop. Therefore, this paper proposes an application scheme of small PLC network based on Siemens S7 communication in cluster control system for glove box-sintering furnace, which can realize stable and reliable unmanned control and management.