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Spreading of nano-droplets is an interesting and technologically relevant phenomenon, where thermal fluctuations lead to unexpected deviations from well-known deterministic laws. Here, we apply the newly developed fluctuating nonideal lattice Boltzmann (LB) method [M. Gross, M. E. Cates, F. Varnik and R. Adhikari, J. Stat. Mech.2011, P03030 (2011)] for the study of this issue. Confirming the predictions of Davidovich and coworkers [Phys. Rev. Lett.95, 244905 (2005)], we provide the first independent evidence for the existence of an asymptotic, self-similar noise-driven spreading regime in both two- (2D) and three-dimensional (3D) geometry. The cross over from the deterministic Tanner's law, where the drop's base radius b grows (in 3D) with time as b ~ t^1/10 and the noise dominated regime, where b ~ t^1/6 is also observed by tuning the strength of thermal noise.

In the present work, three-dimensional computational fluid dynamics analysis is employed to study the droplet dynamics of Newtonian and non-Newtonian droplets impinging on a hot surface under various impact conditions. The Navier–Stokes equations for unsteady, incompressible, and viscous fluid flow are solved using a control volume method. The volume-of-fluid (VOF) technique is also used to track the free-surface of the liquid. The effect of viscosity, density and surface tension on droplet dynamics is evaluated considering their dependence of temperature. The results indicate that the temperature dependence of the both Newtonian and non-Newtonian physicochemical liquid properties must be considered to obtain better agreement of the numerical results with experimental data. After ensuring the accuracy of the numerical methodology, the internal behavior of the droplets is examined, which is shown that the receding velocity of the non-Newtonian droplet is slower than the Newtonian one.

This paper investigates the factors influencing the spread of popular topic competition from the perspective of propagation dynamics. The popularity of a topic is directly influenced by the level of people’s interest in it. The rarity, deviation and type can influence the level of interest in such topics. In addition, the topic publisher also has an impact on the competitive dissemination of the topic. The higher the rank of the original publisher is, the easier it spreads. Compared with small bloggers without fans, it is easier to attract people’s attention, and the heat of the topic will rise faster. The results show that the rarer the topic, the greater the deviation from reality, and the more followers the originator has, the more competitive it is.

Flow visualization experiments had been conducted using a water tunnel to investigate and study the effect of different hole geometries on lift-off and spreading characteristics on a jet in a cross flow stream. The relationships between the hydraulic diameters of the hole geometries and their lift-off and spreading characteristics were also investigated. Eight different hole geometries with the same cross-sectional area were used in the experiments. They are round, square, triangle, rectangular, "rect-circle", "peanut", "V-shaped" and "W-shaped". Dye release injection technique was used to visualize the characteristics of the jet trajectories from different hole geometries. From the results, the different geometries of cooling holes were found to have an effect on the trajectory of the jet. Hole geometries with "tongues" in them such as "W-shaped" and "V-shaped" holes produced jets with better flow adherence but poorer spreading. Hole geometries with lower hydraulic diameters also produced jets with better flow adherence but poorer spreading.

Based on the stress responses of individuals, the susceptible-infected-susceptible epidemic model was improved on the small-world networks and BA scale-free networks and the simulations were implemented and analyzed. Results indicate that the behaviors of individual’s stress responses could induce the epidemic spreading resistance and adaptation at the network level. This phenomenon showed that networks were learning how to adapt to the disease and the evolution process could improve their immunization to future infectious diseases and would effectively prevent the spreading of infectious diseases.

We study the kinetics of specific adhesion of giant vesicles on complemetary (bilayer-decorated) solid surfaces. Tensed vesicles exhibit a single adhesion zone that grows slowly. Floppy vesicles adhere via many small adhesion spots that grow and fuse, merging finally into a large adhesive zone. Using approaches derived from Ref. 12, we show how the progressive mobilization of adhesive molecules (diffusing toward the patch) can explain our experimental observations.

Based on the complex network and non-equilibrium statistic theory, the birth and death equation (BDE) is proposed for the virus spreading on biological networks. This equation, in which the Susceptible Infected Susceptible model is extended, can predict the distribution rule of infection density by generating function. It is a better approach to a real infection process.

This paper is concerned with a diffusive Holling–Tanner prey–predator model in a bounded domain with Dirichlet boundary condition and a free boundary. The global existence of the unique solution is proved. Moreover, the criteria governing spreading–vanishing are derived by mainly using the comparison principle. The results show that if the length of the occupying line is bigger than a threshold value (spreading barrier), then the spreading of predators will make an achievement, and, if the length of the occupying line is smaller than this spreading barrier and the spreading coefficient is relatively small depending on initial size of predators, then the predators will fail in establishing themselves and eventually die out.