Publications by authors named "Baohai Gao"

Aerosol infrared stealth technology is a highly effective method to reduce the intensity of infrared radiation by releasing aerosol particles around the hot exhaust plume. This paper uses a Computational Fluid Dynamics (CFD) two-phase flow model to simulate the exhaust plume fields of three kinds of engine nozzles containing aerosol particles. The Planck-weighted narrow spectral band gas model and the Reverse Monte Carlo method are used for infrared radiation transfer calculations to analyze the influencing factors and laws for the suppression of the infrared radiation properties of exhaust plumes by four typical aerosol particles.

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  • Photoacoustic imaging using gold nanoparticles is gaining attention, particularly due to how their response to light varies with the dielectric constant, which is influenced by both wavelength and temperature.
  • This study employs the Drude-Lorentz model and Mie theory to calculate the dielectric constant and absorption efficiency of gold nanospheres, and uses finite element methods to simulate heat transfer in their surrounding environment.
  • The findings reveal that neglecting the temperature impact on the dielectric constant can result in significant inaccuracies (over 20-30%) in measuring the photothermal and photoacoustic responses, highlighting the importance of considering temperature effects for improved detection technologies and temperature measurement techniques.
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Infrared radiation (IR) characteristics are important parameters for detecting, identifying, and striking military targets in the context of systematic countermeasures. Accurate calculation of IR characteristics for aircraft is significant for the simulation of war situations and the designation of combat strategy. In this work, integrated IR characteristics of aircraft skin and exhaust plume and their interaction are investigated by considering the reflection based on a bi-directional reflectance distribution function and various influence factors such as solar irradiation, ground reflection, aerodynamic heating, and projection radiation from the background.

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As an effective tool for micro/nano-scale particle manipulation, plasmonic optical tweezers can be used to manipulate cells, DNA, and macromolecules. Related research is of great significance to the development of nanoscience. In this work, we investigated a sub-wavelength particle manipulation technique based on plasmonic optical tweezers.

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Photoacoustic (PA) imaging using the nonlinear PA response of gold nanoparticles (GNPs) can effectively attenuate the interference from background noise caused by biomolecules (e.g., hemoglobin), thus offering a highly potential noninvasive biomedical imaging method.

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  • * In cases where reliable information isn't available, two important factors—the thermal accommodation coefficient (TAC) and the fractal-dependent shielding factor—must often be estimated together with PPSD.
  • * A new approach is proposed, combining TAC with the fractal shielding factor to create a "fractal-dependent TAC," which allows for the effective estimation of both PPSD and TAC from normalized LII signals, independent of most other model parameters due to low laser fluence.
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A new technique is developed to retrieve the fractal dimension and size distribution of soot aggregates simultaneously from the relative intensities of multi-wavelength angular-resolved light scattering. Compared with other techniques, the main advantage of this method is its independence of knowing complex refractive index, number density of aggregate, fractal prefactor and primary particle diameter. The forward light scattering procedure of soot aggregate is described by Rayleigh-Debye-Gans polydisperse fractal aggregate (RDG-PFA) scattering theory, and the retrieval process is performed by using the covariance matrix adaption-evolution strategy algorithm (CMA-ES).

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