Composition and particle size of superparamagnetic corrosion products in tap water.

Chemical analyses, magnetization, Mössbauer spectrum, and x-ray diffraction measurements were made on solids removed from tap water by means of membrane filters. The taps from which this water was obtained had previously been unused for prolonged periods of time. When these taps were reactivated and water was first drawn, it was observed that the quantity of coarse solids in the water gradually decreased with flow, while at the same time the quantity of fine solids gradually increased.

Superparamagnetic nanoparticles in tap water.

Magnetization measurements are a useful tool in the characterization of corrosion products formed in municipal water pipes made of iron or steel. Fine particles formed in corrosion processes exhibit superparamagnetic behavior. The size of such particles, which determines their capacity to adsorb hazardous species, can therefore be found from magnetic measurements.

Validation of a novel ultraviolet lidar system with relative Raman-scattering cross sections determined from atmospheric measurements.

We have developed an ultraviolet lidar system in which the upwelled laser beam and the telescope field of view can be made to overlap at any specified location in space. We refer to this system as the Selected Overlap Lidar Experiment. We discuss validation of our system by calculating relative Raman-scattering cross sections (with respect to the nitrogen scattering cross section) for oxygen and water vapor using data collected during field operations of our lidar.