ABSTRACT
Microplasma lamps based on the confinement of a weakly-ionized, low-temperature plasma in a microscale cavity have been found to be ideal for far UV-C radiation at 222 nm (KrCl ∗ excimer). During the last several years, researchers have demonstrated that far UV-C 222 nm efficiently kills airborne pathogens (coronaviruses) with minimal risk of harm to human skin or eyes. Therefore, the data support the premise that far UV-C 222 nm from a KrCl∗ excimer emission in the microplasma flat lamp can be used safely in occupied spaces. In particular, ACGIH recently increased the allowed human exposure levels at 222 nm more than seven times. 1 © 2022 IEEE.
ABSTRACT
The 2022 Roadmap is the next update in the series of Plasma Roadmaps published by Journal of Physics D with the intent to identify important outstanding challenges in the field of low-temperature plasma (LTP) physics and technology. The format of the Roadmap is the same as the previous Roadmaps representing the visions of 41 leading experts representing 21 countries and five continents in the various sub-fields of LTP science and technology. In recognition of the evolution in the field, several new topics have been introduced or given more prominence. These new topics and emphasis highlight increased interests in plasma-enabled additive manufacturing, soft materials, electrification of chemical conversions, plasma propulsion, extreme plasma regimes, plasmas in hypersonics, data-driven plasma science and technology and the contribution of LTP to combat COVID-19. In the last few decades, LTP science and technology has made a tremendously positive impact on our society. It is our hope that this roadmap will help continue this excellent track record over the next 5â€"10 years. [ FROM AUTHOR] Copyright of Journal of Physics: D Applied Physics is the property of IOP Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)
ABSTRACT
Presented observational data indicate that a significant number of infections with the SARS-CoV-2 coronavirus occur by air without direct contact with the source, in addition, in a tangibly long time interval. It is noticed that atmospheric precipitations help to cleanse the air from pollution and at the same time from viruses, reducing non-contact infections. These facts additionally actualize the problem of optimal microbiological decontamination of air and surfaces. In order to optimize microbiological sterilization, a thermodynamic approach is applied. It is shown that irreversible chemical oxidation reactions are the shortest way to achieve sterility, they being capable of providing one hundred percent reliability of decontamination. It is established that oxygen is optimal as an oxidant, including ecologically, because it and all of its reactive forms harmoniously fit into natural exchange cycles. The optimal way to obtain reactive oxygen species for disinfection is the use of low-temperature (“cold”) plasma, which provides energy-efficient generation of oxidative reactive forms - atomic oxygen (O), ozone (O3), hydroxyl radical (⋅OH), hydrogen peroxide (H2O2), superoxide (O2 −), singlet oxygen O2(a1Δg). Due to the short lifetime for most of the above forms outside the plasma applicator, remoted from the plasma generator objects should be sterilized with ozone (O3), the minimum lifetime of which is quite long (several minutes). It is substantiated that microwave method of generating oxygen plasma is optimal for energy efficient ozone production. A modular principle of generation is proposed for varying the productivity of ozone generating units over a wide range. The module is developed on the basis of an adapted serial microwave oven, in which a non-self-sustaining microwave discharge is maintained due to ionizations produced by radionuclides-emitters. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.
ABSTRACT
SARS, MERS, SARS-CoV-2 and other pathogens have caused many pandemics in the world. These pathogens are often spread as aerosols in the air. Thus, fast, efficient air disinfection is essential for effectively limiting the spread of the pathogens. A low temperature plasma disinfection method that deactivates many kinds of bacteria, fungi, viruses, spores and other microorganisms has attracted much attention due to its efficiency and environmental friendliness. Disinfection methods can be divided into physical disinfection, chemical disinfection and comprehensive disinfection based on their key factors. This paper reviews the disinfection mechanisms, application scenarios, development progress and other characteristics of various disinfection methods. The review then focuses on the application of these technologies to the disinfection of pathogens such as SARS-CoV-2 with emphasis on plasma disinfection including the key methods and prospects of plasma disinfection in central air conditioning systems. Finally, the Gong Zi Ting performance center of Tsinghua University is used as an example to show the practicality of this surface discharge plasma disinfection method as an example for further applications. This method can significantly improve epidemic prevention and control, as well as the construction of national biosafety systems. © 2021, Tsinghua University Press. All right reserved.