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Evaporator plays a key role in indirect refrigeration system, so improving the efficiency of evaporator is of great significance to improve the overall performance of refrigeration system. For the plate and shell evaporator, the reliability of the model is proved by numerical simulation of the existing evaporator and comparison with the experiment. An improved scheme is proposed for the existing evaporator, and the improved model is simulated and analyzed. The result shows that compared with the previous model, the improved model improves the heat exchange efficiency, reduces the pressure drop, and improves the overall efficiency of the evaporator.

The damage effect of PTFE/Al/W reactive fragment impacting partially-filled fuel tank is investigated by combining the ballistic gun experiment and theoretical analysis. The experimental results show that, with the impact velocity ranging from 806m/s to 1331m/s, the reactive fragments successfully perforate the front plate of fuel tank and cause the flash-ignition of fuel/air mixture, but the fuel tank does not fail obviously. Based on the experimental results, a temperature analysis model of reactive debris is developed by combining the energy release characteristic of reactive material and the convective heat transfer model. The model result shows that the high-temperature reactive debris can effectively ignite fuel/air mixture, which is in good agreement with the experimental results.

To improve the damage performance of the shaped charge when damaging the concrete target, a new structure of shaped charge with reactive material composite liner was proposed. The behavior of reactive material composite liner-shaped charge penetrating the concrete target was researched by numerical simulation in the finite element simulation platform Autodyn-2D. The effects of the ratio of liner diameter and the ratio of the liner thickness of the inner liner to the composite liner on the penetration depth, hole diameter, and the following behavior of reactive materials were obtained. Numerical simulations show that, with increasing the liner diameter ratio and the liner thickness ratio, the penetration depth and hole diameter of the composite jet into concrete first increase and then gradually decrease. However, the increase of the liner diameter ratio and thickness ratio also means a decrease in the reactive materials’ total mass, which will significantly affect the following reactive materials into the penetration hole. Simulated results further show that it is better to find out that the liner diameter ratio is 0.7 and the liner thickness ratio is 0.2~0.4. The penetration depth and hole diameter of the composite jet into the concrete match well with the quality of the following reactive materials.

Comprehensive energy metering and electricity market-oriented transactions under the dual carbon goals put forward higher requirements on the accuracy of metering equipment clocks. The existing inventory of metering equipment has complex specifications, complex communication methods, and difficult management. Because of different production years, the old version of the metering equipment has poor clock retention capability and insufficient automatic time synchronization function. In order to solve the problems of clock accuracy and time management of metering equipment, a wide-area hierarchical collection and synchronization technology of clocks is designed, a technical framework for clock collection and synchronization of equipment at all levels of the system is constructed, and the normal state of system equipment is strengthened and maintained through the method of serial broadcast time calibration. Clock, designed a time-calibration protocol for object-oriented metering equipment. This technology has been applied to the clock management of on-site metering equipment, and the qualified rate of metering equipment clocks has reached more than 95%, which has improved the automation level of metering equipment clock management, the efficiency of time schooling, and the timely rate of time schooling.

Surface acoustic wave (SAW) resonator with outstanding quality factors of 4829/6775 at the resonant/anti-resonant frequencies has been demonstrated on C-doped semi-insulating bulk GaN. The impact of device parameters including aspect ratio of length to width of resonators, number of interdigital transducers, and acoustic propagation direction on resonator performance have been studied. For the first time, we demonstrate wireless temperature sensing from 21.6 to 120 °C with a stable temperature coefficient of frequency of –24.3 ppm/°C on bulk GaN-based SAW resonators.

In addition to non-radiative guided modes, two-dimensional photonic-crystal slabs support guided resonant ones which can radiate into free space. From the polarization states of these guided resonances, a polarization field on a photonic band can be constructed in momentum space. Momentum-space polarization fields display complicated configurations and patterns with different types of polarization singularities inside, shedding new light on the manipulations of light flows. In this review, we summarize the recent research progress on momentum-space polarization fields and singularities in two-dimensional photonic-crystal slabs, focusing on their unique optical properties and potential applications as well.

Quantum controlled teleportation is the transmission of the quantum state under the supervision of a third party. This paper presents the theoretical and experimental results of an arbitrary two-qubit quantum controlled teleportation scheme, in which the sender Alice only needs to perform two Bell state measurements and the receiver Bob can perform an appropriate unitary operation to reconstruct the arbitrary two-qubit states under the control of the supervisor Charlie. The operation process of the scheme is verified on the IBM quantum experience platform, and the accuracy of the transmitted quantum state is further checked by performing quantum state tomography. Meanwhile, a good fidelity is obtained by using the theoretical density matrix and the experimental density matrix. A sequence of photonic states is introduced to analyze the possible intercept–replace–resend, intercept–measure–resend, and entanglement–measure–resend attacks on this scheme. The results proved that our scheme is highly secure.

AC-FSM is a new technology of external monitoring the internal corrosion for oil and gas pipelines. The current source stability of the FSM equipment is one of the important factors affecting the monitoring accuracy. According to the equipment requirements, a precision current source with adjustable frequency is designed. With C8051MCU as the control core, DAC conversion and differential amplifier are used to control the frequency and the current amount. The experiment shows that the output of excitation power supply has good consistency, the changing range was less than 0.3 %. When the temperature changes, under the condition of low frequency 5Hz, the change of current is less than 0.5 %, under the condition of high frequency 102Hz, the change of current is less than 0.4 %, which avoids the influence of temperature drift. This equipment is suitable for the long period operation of oil and gas pipelines in the field.

Thin-film transistor (TFT) active matrix (AM) arrays have been developed to achieve many applications, including flat panel displays, digital x-rays, digital microfluidics (DMF) and high-throughput biosensors. Here, we focus on a review on TFT array technologies for biological sensing systems, which are regarded as one of the most promising emerging application fields of TFTs. As an important part of the biological sensing system, the DMF chip will be introduced. In particular, development of the TFT-based AM DMF (AM-DMF) chips, which possess the characteristics of higher throughput and higher flexibility of manipulating liquid samples, will be discussed in details. Further, the developed TFT array based biological sensing systems will be summarized and discussed as well. Finally, we present prospects for AM-DMF chips and biosensors, along with a brief conclusion.

For the experiments of testing the Newtonian inverse-square law (ISL) at short range, we have analyzed the residual gas damping effect under the assumption of the temperature of the gas is isothermal (Ke J et al 2020 Class. Quantum. Grav. 37 205008). However, when the test mass squeezes the gas, the temperature of the gas will change accordingly and may cause additional noise. It is essential to study this phenomenon in pursuit of higher precision test of ISL. Here, we discuss the non-isothermal squeeze film damping by using the differential equations of energy conservation and change in molecular density. The results show that this kind of Brownian motion torque noise is larger than that estimated previously and is influenced by the degrees of freedom of molecules. Namely, a larger accessible distance between test bodies is needed in comparison to the internal damping of the pendulum.

Aiming at the problem that the 6-DOF manipulator can quickly avoid obstacles in high-dimensional space, the method of path planning based on the improved rapid expansion random tree (RRT) algorithm is proposed. The improved RRT algorithm combines the advantages of the target bias strategy and proposes a method for setting the intermediate bias point. In random sampling, the sampling point is biased to the intermediate bias point,with a certain probability to reduce the blindness of sampling, and use at the same time the path shortening method reduces path nodes and turning points, and optimizes the motion path of the robotic arm. By comparing the simulation results with the RRT and P-RRT algorithms, the effectiveness of the improved RRT algorithm in the calculation time and the number of path nodes is proved.

In the dual manipulator motion planning of live working robot, the traditional motion planning algorithm has the problems of too many turning points and non-smoothness. Therefore, this paper proposes a method of reverse splitting and local interpolation to remove redundant path nodes and optimize the motion trajectory. The working scene of overhead distribution line live working robot is simulated in MATLAB robot toolbox. The model includes manipulator R, manipulator L and overhead conductor to verify the effect of the method proposed in this paper. The results show that, the proposed method ensures that the redundant path nodes are removed on the premise of no collision between the two manipulators, which significantly improves the quality of the path.

Currently, pointer meters in substations are read manually, which causes a waste of human resources. To realize automatic reading of such meters, an accurate method for recognizing and reading of pointer meters was proposed for the inspection robot in substation. The new method consists of three steps. Step 1: the image is preprocessed with grayscale, noise reduction and piecewise linear grayscale transformation. Step 2: the Gaussian scale space is used to enhance the scale invariace of the ORB algorithm. Meanwhile, the RANSAC algorithm is used to screen the matching point pairs, which improves the accuracy of the feature pointer matching. Step 3: the Hough transform algorithm is utilized to fit the pointer. Finally, the reading result is obtained according to the angle method and the prior information of the pointer meter. The proposed approach can recognize and read the meter accurately. It has high reliability and engineering application value.

With the continuous development of our economy, the types and quantity of engine bearing are increasing. In order to prevent the bearing moving in the bearing pedestal, one or both ends of the bearing need to make positioning lip for axial positioning. In order to meet the needs of mass bearing production, an auto loading device for positioning lip of bearing is proposed in this paper. The horizontal conveyor belt and loading guide are used to make the blank turn to the required angle, and then the double cylinder valve and push rod motor are used to realize the time-sharing conveying and continuous loading of the blank. During the loading process, there are inclined slideway and blocking plate to avoid the collision between blanks and ensure the reliable loading bearings. Through the actual production verification, the developed device has the advantages of simple structure, low cost, fine working stability, and made great improving in the efficiency and safety for production of bearing.

Glucose oxidase-mediated starvation therapy that effectively cuts off energy supply holds great promise in cancer treatment. However, high glutathione (GSH) contents and anoxic conditions severely reduce therapy efficiency and cannot fully kill cancer cells. Herein, to resolve the above problem, this study constructed a biomimetic nanosystem based on nanreproo-MnO2 with porous craspedia globose-like structure and high specific surface area, and it was further modified with dopamine and folic acid to guarantee good biocompatibility and selectivity toward cancer cells. This nanosystem responsively degraded and reacted with GSH and acid to regenerate O2, which significantly increased intracellular O2 levels, accelerated glucose consumption, and improved starvation therapy efficiency. Moreover, anticancer drug of camptothecin was further loaded, and notably enhanced cancer growth inhibition was obtained at very low drug concentrations. Most importantly, this novel therapy could unprecedentedly inhibit cancer cell migration to a very low ratio of 19%, and detailed cell apoptosis analyses revealed late stage apoptosis contributed most to the good therapeutic effect. This work reported a new train of thought to improve starvation therapy in biomedicine, and provided a new strategy to design targeted nanocarrier to delivery mixed drugs to overcome the restriction of starvation therapy and develop new therapy patterns.

An important part of the low-frequency cable network spacecraft, in order to improve the efficiency of the spacecraft’s low-frequency cable network assembly process, according to the characteristics of the spacecraft cable network, based on the three-dimensional digital design of the spacecraft cable network, the spacecraft based on the three-dimensional model. The design and optimization of the cable network final assembly, a digital cable network final assembly was proposed to achieve the purpose of improving the efficiency and reliability of the cable network final assembly.

In radar signal processing, radar target parameter estimation is one of the important tasks of radar target detection. Multipath effect is one of the main error sources of satellite navigation system. In the existing research, the method based on maximum likelihood estimation criterion is considered as the best multipath suppression technology, but its calculation is particularly complicated when there are multiple signals and the number of paths is unknown. This paper mainly studies the application of sparse representation theory in radar target parameter estimation, taking Doppler frequency estimation as an example. The sparse model of Doppler frequency estimation is established, and the frequency estimation is carried out by the classical greedy iterative reconstruction algorithm, and high resolution is obtained. In this paper, a variable step-size fitting algorithm is adopted, which is simple and practical, has little computation, is independent of multipath number, is easy to realize and is easy for real-time signal processing.

In the troposphere, the destruction of ozone and the formation of new particles are closely related to the iodine content, which mainly comes from iodide (I−) and iodate ( IO 3 − ) in the seawater. Therefore, understanding the interactions between I−, IO 3 − and water molecules plays a certain role in alleviating the destruction of the ozone layer. Raman spectroscopy is commonly used to obtain the information of the interaction between I−, IO 3 − and water molecules quickly and accurately. Herein, the effect of I− and IO 3 − on the change in Raman band characteristics of water is investigated to reflect the associated intermolecular interactions change. With the addition of the two ions, the Raman band corresponding to OH stretching vibration moves towards the high wavenumber, indicating the formation of hydration structure. The narrowing of the Raman band from OH stretching vibration under weak hydrogen bond agrees well with the hydrogen bond variation, while the abnormal broadening of the Raman band from OH stretching vibration under strong hydrogen bond indicates the formation of H-down structure. With the increase of ions concentration, the frequency shift of the Raman band from OH stretching vibration under both weak and strong hydrogen bonds becomes more apparent. Meanwhile, the frequency shift of I− is more obvious than that of IO 3 − , which indicates that I− is more likely to form the hydration structure with water than IO 3 − . These results contribute to analyzing the different interactions between I−–water and IO 3 − –water, then helping to prevent ozone depletion.

In order to explore the effects of different fertilization treatments on soil properties and crop growth during the maturation of raw soil, a pot planting experiment with different fertilization treatments was carried out. Three fertilization treatments were set up in the experiment: single organic fertilizer treatment (OF), pollution-free fertilization treatment (NP), and conventional fertilization treatment (CF). The compactness of different soil layers,maize plant height, Chlorophyll value and above-ground biomass under the three fertilization treatments were measured. The experiment results showed that: compared with CF treatment, OF and NP fertilization treatment can better improve soil compaction and increase the plant height and leaf green value of maize, the chlorophyll value of maize under OF and NP treatments increased by 22.6% and 10.6%, and the plant height of maize increased by 58.0% and 31.8% respectively. The order of the magnitude of change of soil compaction in different soil layers was CF> NP> OF. Under conventional CF treatment, the maximum compactness value of 20 cm soil layer was 1426 kPa. For the aboveground biomass of maize, the aboveground biomass of maize under OF and NP fertilization treatments were significantly higher than that of CF fertilization treatment (P

Incineration is an important way of garbage disposal. The fly ash is a kind of hazardous waste, which is rich in heavy metals, dioxins and other harmful substances. At present, the main treatment and disposal technologies of fly ash include stabilization and solidification, chemical treatment, safe landfill and resource treatment. At present, the main treatment technologies have their own advantages and disadvantages. This paper summarizes the treatment and disposal methods of fly ash based on the research status at home and abroad. Among them, resource-based treatment is the main research direction in the future. It is urgent to study clean and efficient treatment technology suitable for China.

The environmental investigation, sampling analysis and health risk assessment were carried out on the soil contaminated by As-containing chemical warfare agents (CWAs) from Japanese abandoned chemical weapons (JACW) in Northeast China, referring to “Technical Guidelines for Risk Assessment of Soil Contamination of Land for Construction”. The results indicated that the arsenic content in the contaminated sites exceeded the risk screening value. The health risks resulting from oral exposure were higher than those of other exposure pathways, and exceeded the acceptable level of human body. Therefore, the contaminated land must be carried out the soil remediation to reduce the risk to the acceptable level of human health before site development.

This paper investigates the structure design problem for the thermocouple junction in spacecraft thermal vacuum tests. Due to the different configurations during the tests, the length and the number of thermocouples are always different, which would lead to certain cost. As a result, a novel thermocouple integrated junction structure is developed and the thermocouple wire can be re-used. The experiment demonstrates that the proposed design method can save the spacecraft thermal vacuum test cost and considerably improve the test efficiency.

After the implementation of the project of returning farmland to forest and ditching and rebuilding land in Yan’an area, the hydrological process in the basin has changed. In order to clarify the dynamic characteristics of groundwater, a typical Nanniwan basin was selected, and groundwater monitoring equipment was installed in the upstream, middle and downstream respectively. The dynamic changes of groundwater in the basin. The results show that among the annual precipitation in the small watershed of the Loess Plateau, June-August (summer) is the wet season, with the most concentrated precipitation, with a total precipitation of 451.8 mm, of which August has the largest precipitation; the groundwater depth gradually increases before September. After September, the upstream and downstream water levels begin to stabilize or rise; the upstream groundwater level fluctuates slightly; the shallow groundwater areas in the middle reaches have large fluctuations due to the large water users; the groundwater depths in the downstream areas are generally between the upstream and Between the middle reaches, the depth of burial showed a slight increase overall.

This article analyzes the changes in water resources, water consumption, and water structure in Shaanxi Province, China from 2004 to 2018, based on the water resources bulletin data of Shaanxi Province. The results show that the inter-annual differences in the amount of water resources in Shaanxi Province in the past 15 years are obvious, and the change process of the amount of surface water resources is basically the same as that of the total amount of water resources. The amount of water resources varies greatly around 2012; the total amount of water used in Shaanxi Province and various types of water consumption have shown a significant upward trend. Among all types of water consumption, agricultural water consumption has the largest increase, with a linear trend rate of 38 million m3/a. The proportion of agricultural water used in various types of water shows a significant downward trend, and the proportion of domestic water and ecological water shows a significant upward trend.

The paper designed and built a simulation reaction system for the Wet Flue Gas Desulfurization(WFGD) process to analyze the effects of factors on the Oxidation reaction of SO2 for the reuse of reclaimed water sludge. Six trace components including magnesium, iron, chloride, aluminum, PAM and PFS in reclaimed water sludge from reclaimed water softening were selected for analysis factors. The effects of six factors on the oxidation reaction were tested by single factor experiments. The multi-factor effects on the oxidation reaction was studied by adding different proportion of reclaimed water sludge to the desulfurizer of the simulated reaction system. In addition, the effect of reclaimed water sludge on the crystallization and dehydration of desulfurization slurry was analyzed. The results show that six factors have little effects on the SO2 oxidation rate in the test range. The addition of reclaimed water sludge has a significant effect on the crystalline form and dehydration of gypsum.

The establishment of food traceability supply chain is an effective way to solve the problem of food safety. But the cost of operating traditional food traceability supply chain system is high. The enterprise on the chain are not willing to participate, and the data on the chain is easy to falsified, which leads to the existence of food traceability and the lack of consumers’ willingness to buy for it. Based on this, solving the high cost in the technical point has become a feasible meaning. Introducing blockchain technology into food safety traceability can improve brand reputation, maintain market and consumer confidence, improve supply chain management, accelerate product and reduce liability risk. In this paper, from the compatibility of block technology and food traceability supply chain, it is concluded that the introduction of blockchain technology will reduce the transaction cost, quality cost, time cost, activity cost, and supply chain traceability additional cost in the food supply chain cost. By comparing with the application cost of block chain technology, this paper explores the cost control mechanism of food traceability supply chain based on block chain, so as to promote the development of food traceability supply chain. The application of blockchain technology in food traceability supply chain will improve the food traceability supply chain system.

In this study, the horizontal cooling performance of piezoelectric fans was evaluated numerically. The flow field, average heat transfer coefficient and average temperature were estimated, and the best performance was found to be at (h/Lb=1/20).The experimental results showed that height reduction of the piezoelectric fan to a certain extent could improve the heat transfer performance. However, when the distance between the fan and the heating wall was too small (h/Lb

For the iron-based powder metallurgical friction pair under high-speed braking conditions, the structural model and physical model of the friction pair were established, and the finite element software ABAQUS was used to calculate and analyze the temperature field and distribution law of the friction pair during friction braking. The results show that during friction braking, the temperature at the outer diameter of the contact surface of the friction pair is the highest, and the temperature at the inner diameter of the edge of the chip removal tank is the lowest. During braking, the temperature of friction pair increases first and then decreases with time.

In view of the iron-based powder metallurgy friction pairs under braking conditions, the temperature field and stress field of friction pairs under different rotation speeds were calculated by using the finite element software ABAQUS through building the structure and physical model of friction pairs. The temperature and stress distribution of the friction pairs under different rotation speeds were studied. The results show that in the process of friction braking, the temperature at the middle diameter of the friction contact surface is higher, and the stress at the inner diameter of the friction contact surface is the largest. With the increase of rotation speed, the distribution of temperature and stress is not changed.

The material model was established by the finite element analysis software ABAQUS. The temperature field and stress field of iron-based powder metallurgy friction pairs under the brake pressure of 0.44Mpa and 0.8MPa were calculated respectively. The variation laws of temperature and stress under two pressure conditions were compared and analyzed. The results show that with the increase of braking pressure, the stress of the friction pairs increases, but the distribution of temperature and stress fields changes little.

For small sample data, data expansion is an effective means to improve the accuracy of target recognition. To image magnification to enhance image resolution as a starting point, the author puts forward two kinds of image magnification method based on wavelet transform. Qualitative analysis on the experimental data and quantitative analysis using average gradient, cross entropy as performance index, show that the proposed image magnification method has obvious advantages in terms of image definition, maintaining image gray scale information. Finally, the author proposes the method of image expansion based on the image magnification data of the four methods, which greatly enriches the diversification of the training set on resolution, clarity, contrast, integrity and so on, and theoretically analyzes the feasibility of improving the recognition accuracy of the data with few samples and small targets.

With the rapid development of integrated energy system and microgrid technologies, aiming at the operational safety problems caused by the uncertainty of the sources and loads, this paper proposed a robust optimal scheduling model of the multiple integrated energy microgrids considering sources and loads uncertainty. In order to minimize the total operating cost of the multiple microgrids, the interconnection lines were introduced into the multiple microgrids for joint operation, on the basis of renewable energy outputs and multi-energy loads prediction, the uncertainty of sources and loads were characterized and the established model were solved. The results of an example showed that the proposed method can effectively improve the economy of multiple microgrids and reduce the risk caused by the uncertainty of sources and loads, thus verified the effectiveness and feasibility of the proposed method.

This paper investigates the suitability of CdTe photovoltaic cells to be used as power sources for wireless sensors located in buildings. We fabricate and test a CdTe photovoltaic cell with a transparent conducting oxide front contact that provides for high photocurrents and low series resistance at low light intensities and measures the photovoltaic response of this cell across five orders of magnitude of AM1.5G light intensity. Efficiencies of 10% and 17.1% are measured under ~1 W m-2 AM1.5G and LED irradiance respectively, the highest values for a CdTe device under ambient lighting measured to date. We use our results to assess the potential of CdTe for internet of things devices from an optoelectronic, as well as a techno-economic perspective, considering its established manufacturing know-how, potential for low-cost, proven long-term stability and issues around the use of cadmium.

Reclaimed soil in hollow villages can be used to supplement cultivated land resources. In this study, reclaimed soil in hollow villages in Chengcheng County was selected as research object, and a combination of field investigation and indoor analysis was used to evaluate the cultivability of the reclaimed soil. Specific indicators for evaluation were borrowed soil thickness, Physical and chemical properties of soil, design of piece of farmland, crop growth indicators, convenience of farming, irrigation conditions, the mechanization degree. The research results have important reference significance for evaluating the quality and cultivability of the reclaimed soil.

Aiming at the problems of soil poor and the decrease of cultivated land in the alluvial fan area in the northern slope of the Qinling Mountains, the selection of suitable alternative soil-forming materials to improve the soil in the piedmont area could provide a scientific reference for the improvement of soil quality. Therefore, we chose six different alternative soil-forming materials treatments, including vermiculite (M1), perlite (M2), clay shale (M3), gravel (M4), sand (M5), and soft rock (M6), which mixed with soil at a ratio of 0.5 L·m2 for field soybean planting experiments, respectively. The results showed that the order of soybean plant height from high to low in 6 different alternative soil-forming materials was M2> M6> M3> M5> M4> M1, the chlorophyll value of M2 and M3 was larger than that of the other four treatments, and the range of increase was 20.9%-26.6%, the figures showed M2 treatment was the most suitable for soybean plant growth. For soybean root dry weight, 100-grain weight and yield, the soybean root dry weight, 100-grain weight and yield under M2 and M1 treatment were larger. Comprehensive analysis of crop growth indicators and yield showed that M2 treatment was the most suitable as an alternative soil-forming material for soybean growth and soil improvement in mountainous areas.

The Chinese Fusion Engineering Testing Reactor (CFETR) aims at providing technical support and data reference for future fusion demonstration reactor. The vacuum vessel primary heat transfer system (VV PHTS), playing a vital role in guaranteeing the safety operation of tokamak device, which is a part of the tokamak cooling water system. It will operate in three main modes: plasma operation, water baking and decay heat removing. The design of the VV PHTS should have three functions corresponding to the above modes. Based on the thermal-hydraulic requirements, the system process have been proposed. The concept design of the system has been performed including pipes and pressurizer. For the purpose of obtaining the parameters of other main components and predicting the system operating behaviour, the thermal-hydraulic analysis model has been developed by using AFT fathom mode. The steady-state results of all three operating modes such as velocity and pressure show that the designed VV PHTS and selected methodology are feasible.

Aiming at the uncertainty output of intermittent energy stations in new ecological energy towns, this paper proposes a risk trading scheme based on the cooperative game mode of multi-energy station main interests. Combining wind power and photovoltaic power generation through the risky electricity trading between different energy stations and take full advantage of the natural complementarity between wind and solar energy in time and region, which is expected to reduce the risk of wind power and PV forecast deviation. At the same time, in view of the different load characteristics of cold/heat/electricity and play the coordination and complementary capabilities, which can realize coordinated control of new ecological energy stations. Finally, the proposed method are verified by simulation.

Near-equiatomic NiTi is known to exhibit multiple martensitic allotropes, including B19′, B19″ and base-centred orthorhombic (BCO). Formation of these martensites is associated with volume expansions, thus hydrostatic loading has direct influence on the stability, ground-state, transformation pathways and the structures of these phases. This work was conducted to clarify some uncertainties in the literature concerning the effect of hydrostatic tension on these properties of the martensite allotropes using the generalised solid-state nudge elastic band method implemented in density functional theory. It was found that higher hydrostatic compression favours phases of lower specific volumes, and higher hydrostatic tension favours phases of higher specific volumes. B19′ is stable at above 2 GPa compression, B19″ is stable within -6 GPa tension and 6.6 GPa compression and BCO is stable between -8 GPa tension and 8.8 GPa compression.

This article uses powder metallurgy technology to prepare foamed aluminum and carbon nanotubes (CNTs) / foamed aluminum composites. The laser thermal diffusion analyzer, thermal analyzer, and transfer function sound absorption coefficient test system were used to study the thermal conductivity and sound absorption properties of aluminum foam and its composites, respectively. The results show that the thermal conductivity of aluminum foam with 79% porosity is only 5W · m−1·K−1, which is much smaller than the thermal conductivity of aluminum. So it can be used as an ideal thermal insulation material; The thermal conductivity of carbon nanotubes (CNTs) / foamed aluminum-based composites increases first and then decreases with the increase in the mass fraction of CNTs. As the test temperature increases, the thermal conductivity of the material gradually increases. When the mass fraction of CNTs is 0.75%, the thermal conductivity of foamed aluminum-based composites reaches the maximum. As the test frequency increases, the sound absorption performance of foamed aluminum first increases, then decreases, and then gradually increases, reaching a maximum value around 1000 Hz. The sound absorption performance of CNTs / foam aluminum matrix composites decreases at lower test frequencies as the mass fraction of CNTs increases. At higher frequencies, as the mass fraction of CNTs increases, the sound absorption coefficient of foamed aluminum decreases first and then increases.

This article uses powder metallurgy to prepare aluminum foam and carbon nanotubes (CNTs) / foam aluminum composites. The effects of the surface treatment of carbon nanotubes, the amount of pore-forming agent, and the amount of carbon nanotubes on the microstructure of aluminum foam and its composites were studied by means of infrared spectroscopy, Raman spectroscopy, and scanning electron microscopy. The results show that the mixed acid treatment of CNTs can effectively disperse CNTs and introduce new functional groups on their surfaces. Using NH4HCO3 as a pore-forming agent and using powder metallurgy, a porosity of 41% to 79%, Cellular pure foam aluminum material and CNTs / foam aluminum matrix composite with 60% porosity.

In this paper, the in-situ scanning electron microscope (SEM) was used to study crack initiation and propagation during the fatigue process of nickel-based superalloys prepared by powder metallurgy at room temperature(RT) and high temperature(HT). It could be found that the crack initiation of alloy is mainly along the direction of crystallographic orientation at room temperature, cracks are parallel, perpendicular, at an angle of 53° and 60°. Cracks initiated in the crystal propagate in zigzag manner at an angle to each other, the direction of growth is perpendicular to the direction of stress. The fatigue cycle required for crack initiation at the grain boundary is much lower than that in the crystal, and the crack propagation is much faster. At initial stage, cracks expand along the grain boundary to a certain extent and then propagate in a transgranular manner, the direction of which is approximately perpendicular to the stress direction. At high temperature, the fatigue crack initiation time is much longer than the room temperature, and the cycle times required for crack initiation at the same stress ratio are 15 times higher than that at room temperature. The time and length of fatigue crack propagation along the grain boundary are larger than those at room temperature, but the length of the transgranular expansion is slightly smaller.

As the satellite design changes from the traditional 2D mode to the 3D digital mode, the satellite assembly also enters the 3D assembly mode. An effective and accurate device installation process information transmission method from designers to operators is not formed, and accidents with incorrect polarity in device installation often occur. In order to improve efficiency and quality of satellite device installation, modelling method of R point of device is regulated and a system based on HoloLens is designed. With the help of the system, the code and R point are clear at a glance, so an ordinary operator can verify the polarity correctness of the device installation and the efficiency can be doubled.

In this paper, the microstructure and frictional wear mechanism of iron based high temperature brake friction materials prepared by powder metallurgy are studied. The results show that iron based friction materials are mainly composed of iron matrix, graphite and hard phase. Under the working condition of rotating speed of 6000r/min, the frictional wear mechanism is mainly abrasive wear and slight oxidative wear. Under the working condition of rotating speed of 8800r/min, the frictional wear mechanism is mainly abrasive wear, adhesive wear and oxidative wear.

Comprehensive Research Facilities in Support of CFETR is aimed to demonstrate a comprehensive research platform with the highest parameters and the most complete functions in the field of magnetic confinement. The cooling water system is an integral part of a comprehensive research platform. The cooling water system includes component cooling water system (CCWS), chilled water system (CHWS) and heat removal system (HRS). The component cooling water system is mainly responsible for transferring the heat load generated by each subsystem during the operation, preventing the system from overheating. This paper presents the thermal hydraulic design of CCWS for Comprehensive Research Facilities in Support of CFETR. Through the development of the thermal hydraulic model of the CCWS, the AFT Fathom code is used to calculate the key thermal hydraulic parameters and predict the thermal hydraulic behaviour. Based on the results of thermal hydraulic analysis, the key thermal hydraulic parameters have been plotted to evaluate the capability of CCWS, such as the required pump head, inlet pressure, flow rate, inlet and outlet temperature and pressure drop of the customer. This paper will provide design guidance for the construction of component cooling water system (CCWS) for Comprehensive Research Facilities in Support of CFETR.