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Nanosecond (ns)‐pulsed air plasmas are promising for environmental and biomedical applications. This paper presented a low‐cost ns‐pulsed plasma system that consists of a two‐stage Cockcroft–Walton voltage multiplier, a spark gap gas switch, and a plasma reactor. This ns power supply generated a uniform air plasma with a volume of 25 × 25 × 2 cm and a maximum ion wind of 0.8 m/s. The ion wind transported aerosols through plasma volume. Aerosols were charged and deposited on the grounded mesh electrode. The direct interactions between reactive ns plasma and deposited aerosols can promote the development of plasma applications. [ABSTRACT FROM AUTHOR]

The COVID-19, viral influenza, tuberculosis, and other widespread infectious diseases evidence that pathogenic biological aerosols (PBAs) are a serious threat to public health. Different from traditional inactivation methods, such as ultraviolet (UV) light which are only safe to use when people are not present, and high-efficiency particulate filters (HEPA) which merely filter microbes without killing them, atmospheric pressure nonequilibrium plasma (APNP) has shown its tremendous potential in drastically diminishing the aerosol transmission route of the infectious agents through the abatement of PBAs. The key issues to develop high performance APNP based air purification system are critically reviewed. Systematic studies on the hazards of different PBAs and the spread of PBAs in indoor environments guide the development of APNP sources to control communicable diseases. The key six sampling and seven detection methods on PBAs are introduced to analyze the PBA abatement efficiency by APNP. Seven common APNP sources which can remove viruses and bacteria aerosols efficiently developed during the past 8 years are introduced. For the APNP sources with small plasma volume, the electric field and diffusion driven charging are the dominant mechanisms to charge PBAs, while the common methods of dusty plasma research can be adapted to atmospheric-pressure conditions to describe the charging effects of APNP sources with large plasma volume. Plentiful long- and short-lifetime reactive oxygen and nitrogen species (RONS) generated by APNP effectively contribute to inactivation of bacterial aerosols. Current studies suggest that viral aerosols are mainly inactivated by short-lifetime RONS including 1O2, ONOO− and ONOOH. The study on the dissolution and reaction of gaseous RONS in microdroplets and accurate measurements on the evolution of charged PBAs are envisaged to be the focus of future research. Opportunities for multidisciplinary collaborative research to advance the development of next-generation high-performance plasma-based air purifiers are highlighted. [ABSTRACT FROM AUTHOR]

Rain enhancement is the main activity field of weather modification in the countries that suffer from water stress. The charged aerosol is a new man-made condensation nucleus to enhance the water vapor condensation. In this article, the negative-polarity air plasma jet array with plasma volume larger than 2 cm3 was used to generate the charged aerosols. Aerosols are mainly charged in the unipolar atmosphere. The averaged charge number of charged aerosols was measured to be 5818e. The attractive electric force of charged aerosols was more than ten times higher than the sum of thermophoretic forces and diffusophoretic forces. These charged aerosols accelerated the collision–coalescence process inside the cloud chamber, generated large droplets in the range of 40–70 μm, and increased the settling amount of moisture by 58.8% [ABSTRACT FROM AUTHOR]

Pathogenic microbial aerosols (PMAs) are significant environmental hazards in built environments, posing a major threat to human health. To combat this issue, we have developed an innovative plasma air filtration system (PAFS) that combines a corona discharge array with a metal foam. The PAFS effectively filters PMAs while simultaneously eliminating microorganisms. Its modular design allows for portability, easy cleaning, and reusability, making it a cost-effective long-term solution. The plasma air purifier (PAP), built upon the PAFS, achieves an impressive filtration efficiency of 91.5 % and successfully inactivates bacteria, fungi, and 99.32 ± 0.15 % of the H1N1 virus in diverse environments. The inactivation mechanisms involve oxidizing bacterial cell membranes and viral envelopes through gaseous plasma reactive species. Additionally, captured aerosols are rapidly evaporated by the ionic wind, leading to pathogen inactivation. The PAP's ozone and ion output adheres to environmental protection standards, making it a promising approach to improve air quality and control airborne infections in built environments. • Plasma inactivates PMA through simultaneous action of physical and chemical means. • The PAFS incorporates a plasma array and a metal foam to capture and inactivate PMA. • The effortless cleaning and reusability of the PAFS lower the operational costs. [ABSTRACT FROM AUTHOR]