Optical attenuation performance of bioaerosols withstanding extreme temperature desiccation stresses

Abstract

Bioaerosols exhibit significant broadband extinction performance and significantly affect climate change, optical detection, communications, and the development of optical attenuation materials. However, it is unclear whether the extinction ability of bioaerosols can withstand extreme conditions such as high temperature desiccation and freezing temperature desiccation. This limits further research on and the application of bioaerosols. Here, we investigate the variations in the composition, functional groups, and protein secondary structure of bioaerosol spores as they withstand extreme temperatures of 60°C and −70∘C. The extinction performance of the bioaerosols withstanding stress is obtained through simulation. Data from an aerosol chamber experiment showed that bioaerosols exhibit significant optical attenuation performance, even after withstanding extreme temperature desiccation stresses. Bioaerosols that withstand both high temperature desiccation and freezing temperature stresses can attenuate the transmittance of incident light in the mid-IR band to approximately 10% and that of incident light in the far-IR band to approximately 25%–35% for 3 min. This study illustrates the significant optical attenuation performance of bioaerosols with respect to extreme temperature desiccation stresses, which broadens the application scenario of bioaerosols as optical attenuation materials and provides a reliable choice for optical attenuation materials in extreme temperatures.

Analysis of optical properties of artificially prepared microbial spores in full optical band

“…Currently, a series of studies have been carried out on the optical properties of microbial spores, for example: Gurton [4] measured the infrared extinction spectra of Bacillus subtilis in 3-13μm waveband and calculated the CRI based on the Mie scattering theory. The research team of Hu [5][6][7][8] constructed a series of calculation models for the extinction performance of microbial spores with different morphological structures and compositions, and also analyzed the effects of environmental factors on the extinction performance [9,10] . Zhao [11] measured the spectral reflectances of three eukaryotic microbe and three prokaryotic microbes in the waveband from 0.25 to 15μm, the complex refractive index was calculated and the FTIR spectra of microbes were analyzed based on the Kramers-Kroning algorithm.…”