## 4 Results
### Results of the Study of Particle Interaction  
For the next part of the study, an analysis of the interaction of a particle with a surface is presented, in which the particle was at a distance of h\({}_{\text{S}}\) = 0.4 nm (Table 2) from the interacting surface at the considered time instance. Based on previous studies [44; 45; 46; 47; 48], it is important to take this distance into account, because, from such a certain distance, the acting force of adhesive attraction becomes sufficient to attract the particle to the interacting surface (in our case, this is the surface of the mycelium). Therefore, when studying the interaction of a pollutant particle with a surface, the velocity value was used, taking into account the previous part of the study of this paper. The velocity value was approximately equal to \(v_{0}\) = 0.3 cm/s (Table 2) near the surface of the tube where the particle was located, so the particle velocity here was much lower compared to the center of the mycelium pore/cylindrical tube (taking into account the cross section). As mentioned before, according to the results of the numerical experiments, the initial velocity of the particle's impact on the plane of the mycelium filter material was 0.3 m/s. The surface was assumed to be flat. Particle velocities in both normal and tangential directions at different angles could be calculated using the following equation:  
\[v_{0}^{N}=sin\varphi_{0};\;\;v_{0}^{T}=cos\varphi_{0} \tag{3}\]  
The initial angles of impact into plane \(\varphi_{0}\) were chosen to be 10\({}^{\circ}\), 20\({}^{\circ}\) and 30\({}^{\circ}\), respectively. At these angles, the initial velocities were as follows:  
When \(\varphi_{0,1}\) = 10, then \(v_{0,1}^{T}\) = 0.29544 m/s; \(v_{0,1}^{N}\) = 0.052094 m/s;  
When \(\varphi_{0,2}\) = 20, then \(v_{0,2}^{T}\) = 0.2819078 m/s; \(v_{0,2}^{N}\) = 0.102606 m/s;  
When \(\varphi_{0,3}\) = 30, then \(v_{0,3}^{T}\) = 0.2598076 m/s; \(v_{0,3}^{N}\) = 0.150 m/s. As a first step in studying the impact of a pollutant particle on the mycelium surface, this study was idealized, and it was assumed that air resistance at an initial distance of 0.4 nm (Figure 2, point S) of the particle from the surface is not estimated/not applicable. Further studies will be devoted to assessing the additional effect of air resistance. Now we would like to present the results. This paper presents the interaction of a glass particle with the surface of the mycelium. The interaction of the particle upon impact on the surface at different angles was studied. The results presented below (Figures 7 and 8) show that, at a small angle, the particle was likely to stick to the mycelium surface. Figure 7a shows the dependence of the force on the displacement after the impact, and when the particle separated, it could not return to the initial distance from which the interaction began. Therefore, having reached point D\({}^{\prime}\) (Figure 2), further movement would involve a sticking process, which was not considered in this work. The velocity value, after reaching this point, was zero (Figure 7f, case 1). At a larger interaction angle, the particle bounced off the interacting surface with the corresponding velocity (Figure 7f, cases 2 and 3). Research shows that, when particles pass through an air filter, their movement at a slight angle to the interacting surface results in sticking. On the one hand, its ability to catch microparticles is a good feature, but the problem of filter clogging time remains. Therefore, further research should focus on both filter clogging and the size of the \"pore/hole\" of the mycelium. The pores must determine both the efficiency and the rate of clogging. The dynamics of the normal force are additionally shown in Figure 7d. It was observed that, as the angle increased, the maximum values of both the normal force and the achieved displacement increased, and the duration of the interaction decreased.