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Ion Composition Of The Topside Equatorial Ionosphere During Solar Minimum, S. A. Gonzales, Bela G. Fejer, R. A. Heelis, W. B. Hanson Apr 1992

Ion Composition Of The Topside Equatorial Ionosphere During Solar Minimum, S. A. Gonzales, Bela G. Fejer, R. A. Heelis, W. B. Hanson

Bela G. Fejer

We have used observations from both the Bennett ion mass spectrometer and the retarding potential analyzer on board the Atmosphere Explorer E satellite to study the longitudinally averaged O+, H+, and He+ concentrations from 150 to 1100 km in the equatorial ionosphere during the 1975–1976 solar minimum. Our results suggest that the ion mass spectrometer measurements need to be increased by a factor of 2.15 to agree with the densities from the retarding potential analyzer and with ground-based measurements. The peak H+ concentrations are about 2.5×104 cm−3 during the day and 104 cm−3 at night and vary little with season. …


Trophic Gradient Analysis Of Lake Powell During Spring Runoff 1992, Wayne Wurtsbaugh Jan 1992

Trophic Gradient Analysis Of Lake Powell During Spring Runoff 1992, Wayne Wurtsbaugh

Wayne A. Wurtsbaugh

Between 26 April and 2 May 1992, students in a utah state university aquatic ecology class visited Lake Powell to do a study of trophic gradients of the reservoir. The main axis of the reservoir was surveyed, as well as less detailed analyses of Moki and Escalante Canyons. The work was conducted in collaboration with personnel from the u.s. Bureau of Reclamation headed by Bill Vernieu, and from the u.s. Geological Survey (Dick Marzolf). Some of their data appear in the physical-chemical section of this report.Each student was responsible for compiling a report on one of the following specific aspects …


Snake River Sockeye Salmon (Oncorhynchus Nerka) Habitat/Limnologic Research, Wayne A. Wurtsbaugh Jan 1992

Snake River Sockeye Salmon (Oncorhynchus Nerka) Habitat/Limnologic Research, Wayne A. Wurtsbaugh

Wayne A. Wurtsbaugh

This report outlines long-term planning and monitoring activities that occurred in 1991 and 1992 in the Stanley Basin Lakes of the upper Salmon River, Idaho for the purpose of sockeye salmon (Oncorhynchus nerka) recovery. Limnological monitoring and experimental sampling protocol, designed to establish a limnological baseline and to evaluate sockeye salmon production capability of the lakes, are present:ed. Also presented are recommended passage improvements for current fish passage barriers/impediments on migratory routes to the lakes. We initiated O. Nerka population evaluations for Redfish and Alturas lakes; this included population estimates of emerging kokanee fry entering each lake in the spring …


Calculation Of Barriers To Proton Transfer Using Variations Of Multi-Configuration Self‐Consistent Field Methods. I. Combinations Of Orbitals, K. Luth, Steve Scheiner Jan 1992

Calculation Of Barriers To Proton Transfer Using Variations Of Multi-Configuration Self‐Consistent Field Methods. I. Combinations Of Orbitals, K. Luth, Steve Scheiner

Steve Scheiner

The usefulness of multiconfiguration self‐consistent‐field (MCSCF) calculations in computing correlated proton transfer potentials is investigated for the systems HF2, H7N2+, H3O2, and H5O2+. In deciding whether to include particular molecular orbitals, it is important to consider the balance of electron density between the donor and acceptor groups and the interactions that are incorporated in the orbitals. Only orbitals which have the proper symmetry to interact with the transferring hydrogen need be included in the MCSCF active space. Reasonable transfer barriers are obtained …


Pulsed‐Laser Excited Differential Photothermal Deflection Spectrometry, Stephen E. Bialkowski, Xu Gu, Pete E. Poston, Linda S. Powers Jan 1992

Pulsed‐Laser Excited Differential Photothermal Deflection Spectrometry, Stephen E. Bialkowski, Xu Gu, Pete E. Poston, Linda S. Powers

Stephen E. Bialkowski

This paper describes a differential photothermal optical absorbance apparatus that uses two excitation beams at different wave-lengths. A single probe beam monitors the difference in heats generated by the two wavelengths. The theory is developed for the operational principles of the apparatus, and theoretical signals are compared with those obtained with a conventional absorption spectrophotometer. The differential photothermal apparatus has a theoretical advantage over conventional spectrophotometry for samples with less than unit absorbance. Experiments are described which verify the operating principles and demonstrate the flexibility of the apparatus.


Experimental Analysis Of Abrasion And Dissolution Resistance Of Modern Reef-Dwelling Foraminifera: Implications For The Preservation Of Biogenic Carbonate, E. Kotler, R. E. Martin, W. D. Liddell Jan 1992

Experimental Analysis Of Abrasion And Dissolution Resistance Of Modern Reef-Dwelling Foraminifera: Implications For The Preservation Of Biogenic Carbonate, E. Kotler, R. E. Martin, W. D. Liddell

W. David Liddell

No abstract provided.


Proton–Donor Properties Of Water And Ammonia In Van Der Waals Complexes With Rare‐Gas Atoms. Kr–H2o And Kr–Nh3, G. Chalasinski, M. M. Szczesniak, Steve Scheiner Jan 1992

Proton–Donor Properties Of Water And Ammonia In Van Der Waals Complexes With Rare‐Gas Atoms. Kr–H2o And Kr–Nh3, G. Chalasinski, M. M. Szczesniak, Steve Scheiner

Steve Scheiner

The perturbation theory of intermolecular forces in conjunction with the supermolecular Møller–Plesset perturbation theory is applied to the analysis of the potential‐energy surfaces of Kr–H2O and Kr–NH3 complexes. The valleylike minimum region on the potential‐energy surface of Kr–H2O ranges from the coplanar geometry with the C2 axis of H2O nearly perpendicular to the O–Kr axis (T structure) to the H‐bond structure in which Kr faces the H atom of H2O. Compared to the previously studied Ar–H2O [J. Chem. Phys. 94, 2807 (1991)] the minimum has more …