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Aiming at the current situation of lack of environment and equipment in radar training, a radar operation training method based on the combination of virtual and real is proposed. Firstly, the connotation of the concept of virtual-real combination is analyzed. Secondly, the interaction methods of combining physical radar and virtual environment and virtual radar and physical environment are studied. Finally, combined with the specific training requirements, the application of real-real, real-virtual, virtual-real, and virtual-virtual radar interaction methods in radar training is analyzed in the same scenario.

This study improves the roller friction experiment platform for monitoring the temperature of flame-retardant conveyor belt in order to realize the early warning of belt conveyor fire.Mass spectrometry is used to analyze the patterns of temperature rise and smoke composition of steel cord flame-retardant conveyor belt in the early stage of friction accident.Results show that as friction progresses, the flame-retardant conveyor belt exhibits symmetrical distribution of surface temperature, where the highest temperature gradually approaches to the center of the conveyor belt and the composition of smoke changes with temperature.The steel cord flame retardant conveyor belt warming process could be divided into three stages according to their warming rate and smoke composition output: stage of oxidation reaction(ambient temperature to 100 ℃), stage of substitution reaction(100~160.2 ℃), and pyrolysis reaction(after 160.2 ℃).The initial stage features low heat capacity of the conveyor belt with quickly-rising temperature, where the products are mostly alkyl and ester compounds.The second stage exhibits gradual increase of heat capacity, slowly-rising temperature, where the products are mostly nitro, ether, and carboxylic acid compounds.The last stage features stable heat capacity of the conveyor belt, the lowest heating rate, where the chlorine-containing compound is detected for the first time in the smoke composition.

A pressurized inhibition method is proposed based on the pre-inhibition process to study the inhibition law and mechanism of the pre-inhibition pressure on the coal spontaneous combustion, with a purpose of enhancing the inhibiting effect of chloride salt inhibitors. In this work, inhibited coal samples were prepared by immersing raw coal in high-temperature and high-pressure reactor at 1 MPa, 2 MPa, 3 MPa, 4 MPa, and 5 MPa, respectively, using MgCl 2 solution with a mass concentration of 20 %. The variation rules of the characteristic parameters, such as the indicator gas concentration, inhibition rate, surface microscopic morphology, and reactive groups, of various coal samples with the elevation of the pre-inhibition pressure were investigated using the programmed temperature-raising oxidation system, infrared spectroscopy, and SEM. It was found that the pre-inhibition pressure was in the range of 1–4 MPa, and with the increase of pre-inhibition pressure, the gas-producing concentration and the content of active groups of coal decreased, and the inhibition rate increased significantly. Increasing the pre-inhibition pressure can significantly improve the inhibition effect, and the optimum pre-inhibition pressure is 4 MPa. Continuing to increase the pre-inhibition pressure will destroy the pore structure of the coal and reduce the inhibition effect. [ABSTRACT FROM AUTHOR]

In this study, nano-silicon carbide (SiC) doped tetradecyl octadecanoate (TO) phase change microcapsules with enhanced thermal energy transfer and storage capacity were prepared through interfacial polymerization. Besides, a series of experiments were performed to comparatively investigate the effects of SiC, hydroxylated SiC (H–SiC), and hydroxylated-silanized SiC (Si–H–SiC) on the morphology, chemical structure, thermal storage performance, thermal stability, cyclic thermal stability, thermal conductivity, and exudation stability of prepared phase change microcapsules. The findings show that phase change microcapsules containing 1 wt% Si–H–SiC exhibit the best performance, as evidenced by their large thermal storage capacity (161.54 J/g) and high encapsulation efficiency (69.03 %). The thermal conductivity of Si–H–SiC-doped phase change microcapsules is up to 0.1167 W/m·k, being 17.6 % higher than that of SiC-doped ones. In addition, they show favorable thermal stability and reliability as no leakage is found after 300 thermal cycles, and they barely leak the core material TO after being kept at 120 °C for 2 h. The reason behind this phenomenon is that Si–H–SiC is doped into the shell of phase change microcapsules through chemical bonds and gets evenly distributed, which greatly improves the interfacial thermal resistance and capsule wall strength of phase change microcapsules. [Display omitted] • Si–H–SiC doped TO microcapsules were synthesized via interfacial polymerization. • The microcapsules have a high thermal energy transfer and storage capacity. • Hydroxylated-silanized SiC improve interfacial thermal resistance and shell strength. • The microcapsules have outstanding thermal stability and reliability. [ABSTRACT FROM AUTHOR]