Self-assembly of gold nanoparticles at the oil-vapor interface: from mono- to multilayers

Alkylthiol-coated gold nanoparticles spontaneously segregate from dispersion in toluene to the toluene-vapor interface. We show that surface tension drops during segregation with a rate that depends on particle concentration. Mono- and multilayers of particles form depending on particle concentration, time, and temperature. X-ray reflectometry indicates fast monolayer formation and slow multilayer formation. A model that combines diffusion-limited segregation driven by surface energy and heterogeneous agglomeration driven by dispersive van der Waals particle interactions is proposed to describe film formation

Self-Assembly of Gold Nanoparticles at the Oil-Vapor Interface: From Mono- to Multilayers.

Alkylthiol-coated gold nanoparticles spontaneously segregate from dispersion in toluene to the toluene-vapor interface. We show that surface tension drops during segregation with a rate that depends on particle concentration. Mono- and multilayers of particles form depending on particle concentration, time, and temperature. X-ray reflectometry indicates fast monolayer formation and slow multilayer formation. A model that combines diffusion-limited segregation driven by surface energy and heterogeneous agglomeration driven by dispersive van der Waals particle interactions is proposed to describe film formation

Self-Assembly of Gold Nanoparticles at the Oil–Vapor Interface: From Mono- to Multilayers

Alkylthiol-coated gold nanoparticles spontaneously segregate from dispersion in toluene to the toluene–vapor interface. We show that surface tension drops during segregation with a rate that depends on particle concentration. Mono- and multilayers of particles form depending on particle concentration, time, and temperature. X-ray reflectometry indicates fast monolayer formation and slow multilayer formation. A model that combines diffusion-limited segregation driven by surface energy and heterogeneous agglomeration driven by dispersive van der Waals particle interactions is proposed to describe film formation

Minimalistic Approach to 3D Obstacle Avoidance Behavior from Simulated Evolution

Abstract. We present a minimalistic approach to establish obstacle avoidance and course stabilization behavior of a simulated flying autonomous agent in a 3D virtual world. The agent uses visual cues, and its sensory and motor components are based on biological principles found in flies. A simple neural network is used for coupling the receptor and effector systems of the agent. In order to achieve appropriate reactions to sensory input, the connection weights are adjusted by a genetic algorithm under a closed loop action-perception condition.

Risky listening behaviour to music via headphones and its determinants – 7.5 years OHRKAN cohort study

To examine risky leisure noise exposure from listening to music via headphones and to identify potential determinants with special focus on portable listening devices (PLDs) among adolescents over a period of 7.5-years. Data were collected by questionnaires at four equidistant time points (O1-O4). Music exposure via headphones was calculated based on self-reported volume setting and listening duration. Exceeding 85 dB(A) equivalent for a 40-hour working week was defined as risky noise exposure. Determinants of risky headphone and PLD exposure were investigated using generalised estimating equations and accounting for missing data by multiple imputation. Closed cohort of 2148 students attending 9th grade of any secondary school type in Regensburg (Germany), during 2009 to 2011. Risky noise exposure from headphone usage was almost twice as high in wave O1 and O2 (at age 15 or 18) compared with 20–23-year-olds in O3 and O4. Risky exposure to headphones and PLDs were associated with younger age, low and medium education, single-parent household and smoking, whereas good self-rated hearing showed a protective effect. Additionally, not being born in Germany was associated with risky PLD exposure. Before harmful behaviours become entrenched, starting preventive efforts at a young age is essential.</p