Kinetic investigation of the hydrolysis of uranium hexafluoride gas.

UF is commonly employed in enrichment technologies and is known to react rapidly with water vapor to form radioactive particulates and hydrofluoric acid vapor. The kinetics of the UF hydrolysis reaction have been observed directly for the first time. The rate appears to be half order and second order for UF and water, respectively, with a rate constant of 1.

Improved measurement for volatile particles: vapor-particle separator design and laboratory tests.

Sampling and measurement of volatile particles is a challenging task. It has been hampered by lack of a reliable technique capable of accurately capturing the phase-partition process of the pollutants without generating bias and artifacts in the data. The objective of this research is to design a new vapor-particle separation technique for performing the phase separation on-line (the sampling aspect), which, simultaneously, enables characterization of the vapors and particles.

Field measurement comparison of aerosol metals using aerosol beam focused laser-induced plasma spectrometer and reference methods.

Several tests were conducted in July 2002 on an instrument developed by researchers at the Oak Ridge National Laboratory (ORNL) for in-situ, real-time measurement of metal-laden aerosol particles in flue gas from combustion facilities. Stock aqueous solutions of prepared metal concentrations were nebulized and injected into the flue gas to provide spikes for the instrument testing. Strengths of the solutions were designed such that a reference method (RM) was able to obtain a sufficient amount of material on filter samples in 30 min cycles; the collected filters were subsequently analyzed in an analytical laboratory using certified methods.

Probing emissions of military cargo aircraft: description of a joint field measurement Strategic Environmental Research and Development Program.

To develop effective air quality control strategies for military air bases, there is a need to accurately quantify these emissions. In support of the Strategic Environmental Research and Development Program project, the particulate matter (PM) and gaseous emissions from two T56 engines on a parked C-130 aircraft were characterized at the Kentucky Air National Guard base in Louisville, KY. Conventional and research-grade instrumentation and methodology were used in the field campaign during the first week of October 2005.

Characterization of carbon-containing aerosolized drugs using laser-induced breakdown spectroscopy.

Aerosolized drug delivery methods have increasingly become popular for pharmaceutical applications. This is mainly due to their ease of application and the more recent advancements incorporating nano-sized generation of particles that find deeper penetration routes and more efficient administration of the drug to specific target organs. Their effectiveness heavily relies on the uniformity of the chemical composition of these aerosolized drugs.

Particle generation by ultraviolet-laser ablation during surface decontamination.

A novel photonic decontamination method was developed for removal of pollutants from material surfaces. Such a method relies on the ability of a high-energy laser beam to ablate materials from a contaminated surface layer, thus producing airborne particles. In this paper, the authors presented the results obtained using a scanning mobility particle sizer (SMPS) system and an aerosol particle sizer (APS).

Intensity-modulated, stepped frequency cw lidar for distributed aerosol and hard target measurements.

A compact frequency-modulated, continuous wave (FM-cw) lidar system for measurement of distributed aerosol plumes and hard targets is presented. The system is based on intensity modulation of a laser diode and quadrature detection of the return signals. The advantages of using laser diode amplitude modulation and quadrature detection is a large reduction in the hardware required for processing and storing return signals as well as the availability of off-the-shelf integrated electronic components from the wireless and telecommunication communities.

Effects of nanophase materials (< or = 20 nm) on biological responses.

Nanophase materials have enhanced properties (thermal, mechanical, electrical, surface reactivity, etc.) not found in bulk materials. Intuitively, the enhancement of material properties could occur when the materials encounter biological specimens.

Monitoring cellular responses of engine-emitted particles by using a direct air-cell interface deposition technique.

The impacts of ultrafine airborne particles generated by diesel or gasoline engines on human lung cells have been investigated using a new in vitro cellular exposure technique. This technique enables direct deposition of the gasoline engine exhaust particles (GEP) and diesel engine exhaust particles (DEP) on human lung cells located at the air-cell interface on a transwell membrane in an exposure apparatus. The cellular responses to particle exposure were measured by the levels of IL-8 chemokines produced as a function of exposure time.