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Gas generators are the functional materials producing gas by combustion. In situations such as pneumatics, fire extinguishing bomb, air bag, deep-water salvage, the gas generators can be ignited to provide power and energy through rapid release of gas. However, the research about gas generators with low water vapor is blank in world. The most widely used gas generators (such as nitroguanidine gas generators) produce a lot of water vapor through combustion, whose liquefaction will cause the reduction of gas pressure. This work selected 4,5-diazolyl-1,2,3-triazole (BTTZ) as gas-generating material. Two kinds of gas generator formulations based on BTTZ with common oxometallate (KNO3) and metal oxide (CuO) were designed. The properties of these gas generator formulations were studied by calculation and experiments. The gas production, gas production rate, water vapor content, compatibility and mechanical sensitivity were measured. The gas specific volume of the formulation 1 was 4.08 m3 kg−1. The clean harmless gas content reaches 93.55%. The water vapor content of the product was 6.08% (volume percentage), which is much lower than the nitroguanidine gas generators (53.47%). Therefore, formulation 1 is a low-water vapor environmental-friendly gas generator as a cleaner production material with practical value.

This work sets focus on producing hydrophobic silica and fire-extinguishing-composition solution into dry water extinguishant powder by high-speed shearing. The solid-to-liquid ratio, different stirring periods and rotational speed were taken into account to analyze their influence on the covering effect. The dry water extinguishants containing ammonium dihydrogen phosphate (ADP) and phosphoric acid are respectively produced added with gel. The jet apparatus is improved for the experiment. According to the results, the phosphoric acid gel dry water extinguishant works best to put out Type-A fire. The ADP dry water extinguishant excels in putting out Type-B fire, equivalent to superfine ABC dry powder extinguishant in terms of effectiveness but with a low cost. For this reason, dry water extinguishant has a broad prospect of application.

The normal pyrotechnically generated aerosol extinguishing agent is effective in extinguishing Class B fire, but have difficulty extinguishing the Class A wood-crib fire. To solve this problem, an experiment has been made in this paper to study the extinction effectiveness of a new type of pyrotechnically generated aerosol extinguishing agent in wood crib fire. Differing from the old ones, the new type of pyrotechnically generated aerosol extinguishing agent generates via combustion of aerosol forming agents containing a kind of phosphorus-containing compound named P90x, which is flammable and has been widely used as fire retardants in materials. P90x was added, for the first time, as a reducer into aerosol forming agents to improve the capabilities against the Class A wood-crib fire. Five aerosol forming agents with the different mass ratio of P90x and potassium nitrate were tested for fire extinguishing efficiency. The fire extinguishing efficiency increased as the amount of P90x increases. And the best fire extinguishing efficiency in this experiment was 20 g/m 3 for wood-crib fire. This new type of aerosol extinguishing agents can adhere to the surface of burning wood and react with it to extinguish fire efficiently. Therefore, the Class A fire (wood cribs) can be extinguished by pyrotechnically generated aerosol extinguishing agents for the first time from all over the world.

At present, the inflatable expansion of a flexible compartment of a spacecraft mainly depends on the compressed gas cylinder. However, there are some problems in the technology of compressed gas cylinders, such as large volume, heavy mass and non-environmental protection. In view of the above problems, a new space inflatable deployment system is innovatively proposed in this work. The system mainly includes a gas generating agent formulation with safety, stability, low combustion temperature, slow gas production, environment-friendly and clean, and a gas generator with simple structure, light weight, small volume and a flexible compartment. The gas released from the system is charged into the flexible compartment of the spacecraft smoothly. Then, the spacecraft flexible compartment is used to carry out experiment and the resulting gas was subjected to test. The results show that the main gas produced by the system is clean and nontoxic nitrogen. In addition, the whole expansion process is stable, slow and smooth. It can be seen that the space inflatable deployment system will have a good application in the field of spacecraft.