The Loihi hydrothermal plume provides an opportunity to investigate iron (Fe) oxidation and microbial processes in a system that is truly Fe dominated and distinct from mid-ocean ridge spreading centers. The lack of hydrogen sulfide within the Loihi hydrothermal fluids and the presence of an oxygen minimum zone at this submarine volcano’s summit, results in a prolonged presence of reduced Fe wi...

Air pollution control devices (APCDs) are not compulsory for medical waste incinerators (MWIs) in developing countries. In South Africa, combustion gases are usually vented directly to the atmosphere at temperatures greater than the formation temperature of dioxin. The possibility of dioxin formation outside the incinerator stack has been hypothesized. A plume model has been developed and teste...

[1] The mantle plume model has been invoked to explain the formation of large igneous provinces (LIP) and associated age-progressive hotspot tracks. The shape of mantle plumes should be significantly altered by physical properties of the mantle and will influence how plume theory is used to interpret observational constraints. Based on theoretical analysis and numerical modeling, we explore the...

BACKGROUND The use of ablative laser treatments is steadily increasing. A side-effect is plume, which can potentially transmit infectious material. Insufficient plume removal may lead to transmission of infectious diseases. OBJECTIVE To introduce a newly developed circular suction technique for ablative interventions. MATERIALS AND METHODS The new plume removal system consists of a circular...

This chapter addresses the key issues of chemical plume mapping and tracing via swarm robots. First, the authors present the models of turbulent odor plumes with both non-buoyant and buoyant features, which can efficiently evaluate strategies for tracing plumes, identifying their sources in two or threedimensions. Second, the authors use the Monte Carlo technique to optimize moth-inspired plume...

—This paper studies the utilization of data gathered from multiple gas sensors placed vertically on a wheeled mobile robot to perform plume tracking strategies. The main research questions to be answered are if is this advantageous and if so, trying to quantify that advantage in terms of plume tracking over traditional two dimensional plume acquisition. This was accomplished by testing a few we...

[1] Inversion of a new data set of teleseismic P-wave travel-times from three PASSCAL seismic deployments around the Yellowstone hotspot reveals a 100 km diameter upper mantle plume that extends from the Yellowstone volcanic caldera to 500 km depth and dips 20 to the northwest. A monotonic decrease in the velocity perturbation of the plume from 3.2% at 100 km to 0.9% at 450 km is consistent wit...

An engineering approach to analyze PM dry deposition due to gravitational settling is summarized in this paper. Particle horizontal settling distance is determined based upon wind speed and particle terminal settling velocity. New PSD in the downwind plume is calculated based upon particle horizontal settling distance and source PSD. Results of this research indicate that change of PSD in the d...

Programmable Thermal Dissociation (PTD) has been used to investigate the chemical speciation of Reactive Gaseous Mercury (RGM, Hg). RGM was collected on denuders and analyzed using PTD. The technique was tested in a field campaign at a coal-fired power plant in Pensacola, Florida. Stack gas samples were collected from ducts located after the electrostatic precipitator and prior to entering the ...

A two-stage computational model of the evolution of a plume generated by laser ablation of an organic solid is presented and discussed. The first stage of the laser ablation involves laser coupling to the target and ejection of the plume and is described by molecular dynamics (MD) simulations. The following stage of a long-term expansion of the ejected plume is modeled by the direct simulation ...