Radiative energy budget estimates for the 1979 Southwest Summer Monsoon

November, 1986.Includes bibliographical references

Satellite inferred surface albedo over northwestern Africa

November 1976.Includes bibliographical references (pages 55-56).Sponsored by the Global Atmospheric Research Program, National Science Foundation and the GATE Project Office, NOAA OCD-74-21678.Sponsored by the Global Atmospheric Research Program, National Science Foundation and the GATE Project Office, NOAA OCD-72-01681 A03

Pyrgeometer data reduction and calibration procedures

May 1976.Pyrgeometer measurements from aircraft, by Bruce Albrecht, Michael Poellot, Stephen K. Cox.Includes bibliographical references (page 48)

Contrasting the Relationships Between Teacher Immediacy, Teacher Credibility, and Student Motivation in Self-Contained and Mass Lecture Courses

Basic communication courses are increasingly taught in mass-lecture formats. Research on teacher verbal immediacy, teacher nonverbal immediacy, teacher credibility, and student motivation has failed to contrast the relationships between these four variables has failed to contrast the relationships between these four variables in different basic course formats. Respondents enrolled in self-contained (n =326) and mass-lecture (n =865) formats of basic communication courses completed surveys measuring these four classroom variables. Results showed that all variables were positively and significantly correlated in both formats. However, four of the six correlation coefficients between teacher verbal immediacy, nonverbal immediacy, teacher credibility, and student motivation were statistically higher in the self-contained format. Verbal immediacy, teacher credibility, and student motivation scores were statistically higher in self-contained formats. These results show that past research has produced some potentially misleading conclusions about these variables. Discussion of the results, suggestions for mass-lecture instructors, and research directions are proposed

Large-scale response of the tropical atmosphere to radiative heating, The

March 1974.Includes bibliographical references.Sponsored by the National Science Foundation GA-36302

GATE phase III mean synoptic-scale radiative convergence profiles

March, 1980.Includes bibliographical references.Sponsored by the Global Atmospheric Research Program, National Science Foundation and the GARP Atlantic Tropical Experiment (GATE) Project Office, NOAA ATM 78-05743.Sponsored by the Global Atmospheric Research Program, National Science Foundation and the GARP Atlantic Tropical Experiment (GATE) Project Office, NOAA ATM 78-12631

Damping and Mass Sensitivity of Laterally Vibrating Resonant Microcantilevers in Viscous Liquid Media

The effect of liquid viscosity and density on the characteristics of laterally excited microcantilevers is investigated and compared to transversely excited microcantilevers. When immersed into a viscous liquid medium such as water from air, the resonant frequency of laterally (in-plane) vibrating microcantilevers is shown to decrease by only 5-10% as compared to ~50% reduction for transversely (out-of-plane) vibrating microcantilevers. Furthermore, as the viscosity of the medium increases the resonant frequency of a laterally vibrating beam is shown to decrease at a slower rate than that of a transversely vibrating beam. The decreased viscous damping also leads to increases in the quality factor of the system by a factor of 4-5 compared to beams vibrating transversely. The mass sensitivities of laterally vibrating beams are also theoretically predicted to be roughly two orders of magnitude larger in water for some cantilever geometries. The increase in the quality factor and mass sensitivity indicate that operating in the in-plane flexural mode (lateral vibration) will decrease the limit of detection compared to operating in the more common out-of-plane flexural mode (transverse vibration). These improvements in device characteristics indicate that microcantilevers excited laterally are more suited for operating in media of high viscosities

The Nikolaevskiy equation with dispersion

The Nikolaevskiy equation was originally proposed as a model for seismic waves and is also a model for a wide variety of systems incorporating a neutral, Goldstone mode, including electroconvection and reaction-diffusion systems. It is known to exhibit chaotic dynamics at the onset of pattern formation, at least when the dispersive terms in the equation are suppressed, as is commonly the practice in previous analyses. In this paper, the effects of reinstating the dispersive terms are examined. It is shown that such terms can stabilise some of the spatially periodic traveling waves; this allows us to study the loss of stability and transition to chaos of the waves. The secondary stability diagram (Busse balloon) for the traveling waves can be remarkably complicated.Comment: 24 pages; accepted for publication in Phys. Rev.

Direct measurement of neon production rates by (α,n) reactions in minerals

The production of nucleogenic neon from alpha particle capture by ^(18)O and ^(19)F offers a potential chronometer sensitive to temperatures higher than the more widely used (U-Th)/He chronometer. The accuracy depends on the cross sections and the calculated stopping power for alpha particles in the mineral being studied. Published ^(18)O(α,n)^(21)Ne production rates are in poor agreement and were calculated from contradictory cross sections, and therefore demand experimental verification. Similarly, the stopping powers for alpha particles are calculated from SRIM (Stopping Range of Ions in Matter software) based on a limited experimental dataset. To address these issues we used a particle accelerator to implant alpha particles at precisely known energies into slabs of synthetic quartz (SiO_2) and barium tungstate (BaWO_4) to measure ^(21)Ne production from capture by ^(18)O. Within experimental uncertainties the observed ^(21)Ne production rates compare favorably to our predictions using published cross sections and stopping powers, indicating that ages calculated using these quantities are accurate at the ∼3% level. In addition, we measured the ^(22)Ne/^(21)Ne ratio and (U-Th)/He and (U-Th)/Ne ages of Durango fluorapatite, which is an important model system for this work because it contains both oxygen and fluorine. Finally, we present ^(21)Ne/^4He production rate ratios for a variety of minerals of geochemical interest along with software for calculating neon production rates and (U-Th)/Ne ages