Studies on the formation and properties of new materials for high-energy, gas-phase lasers are described. Attention is directed mainly to systems having bound excited states but unbound ground states. An important class of such excimer/exciplex systems has a van der Waals dimer/oligomer as its ground state. This research attempts to probe the relative rates of electron pumping of excited-state manifolds and the preferentially pumped vibronic states within each manifold. Reactive quenching of emission, resonant self-absorption of laser emissions, and collision- and noncollision-induced intersystem crossing are also considered. Lists of personnel and facilities are included. 8 figures, 2 tables. (RWR)

This report analyzes data on the health effects of bicycling in an urban environment through intensive study of ten healthy male subjects bicycling or driving in systematically varied conditions in the streets of Washington, D.C. Evaluation criteria for available technology and instrumentation are included and a methodology is developed for route selection. Specific air pollutants (carbon monoxide, ozone, sulfates, nitrates, and particulates) are measured concurrently with exposure and subsequent changes in health status identified through pulmonary function testing, cardiovascular testing, and blood and symptoms analysis. The report concludes that no major adverse short-term health effects were noted for ten healthy male subjects while bicycling or driving in levels of pollution and thermal stress encountered during the study period. Recommendations for further research are also presented.

This study was initiated in 1957 by the U.S. Public Health and many facets of this project are reaching final objectives. Many new studies have developed in the course of this study and will continue. The projects supported by the Energy Research and Development Administration are of utmost importance and consist of: collection of material from uranium miners known to have cancer of the lung into a tumor registry; manual on pulmonary cytology; regression study of sputum cytological findings in uranium miners who showed marked atypical squamous cell metaplasia and have quit smoking cigarettes, mining, or both; continuation of sputum collection and collection of lungs from deceased miners; sensory development for localization of carcinoma in situ of the lung; and lung histology program. Since we have examined approximately 77,000 sputum samples over the last 20 years in cases that showed normal cytology at the inception of the study and some subsequently developed carcinoma of the lung, we have an accumulation of material that is worthy of study and presentation.

Particulate agglomeration and separation at high temperatures and pressures are examined, with particular emphasis on the unique features of the direct-cycle application of fluidized-bed combustion. The basic long-range mechanisms of aerosol separation are examined, and the effects of high temperature and high pressure on usable collection techniques are assessed. Primary emphasis is placed on those avenues that are not currently attracting widespread research. The high-temperature, particulate-collection problem is surveyed, together with the peculiar requirements associated with operation of turbines with particulate-bearing gas streams.