Selected Elastic Moduli of Single-Crystal Olivines from Ultrasonic Experiments to Mantle Pressures

Ultrasonic interferometric measurements, developed for polycrystalline samples in a multi-anvil apparatus, were extended to single-crystal samples of San Carlos olivine and forsterite. The elastic moduli, C22 and C55 of San Carlos olivine and C55 of pure forsterite, were measured to about 13 gigapascals. These data on C22 for San Carlos olivine and C55 for forsterite are consistent with earlier measurements and extrapolations. The C55 for San Carlos olivine increases linearly as a function of increasing pressure, unlike the earlier nonlinear behavior observed at high pressure with impulsive stimulated scattering techniques.     

Effect of Excessive Calcium Applications on Growth and Postharvest Performance of Bedding-plant Impatiens

ABSTRACT

Application of excessive amounts of calcium (Ca) during the production cycle improves the quality and postharvest life of several florist crops. Most bedding plants are fertigated with Ca at 100 to 200 mg L^{? 1}throughout the production cycle, but we do not know the effects of higher Ca concentrations. The objective was to evaluate the effect of application of excessive Ca (≥ 280 mg L^?1) supplied during the production cycle on the growth, development, and subsequent postharvest performance of bedding-plant impatiens (Impatiens wallerana Hook. f. ‘Super Elfin White’) under simulated retail conditions. Calcium was applied at 120, 200, 280, 360, and 440 mg L^?1 during each fertigation during the growing cycle. The total nitrogen (N) concentration was 150 mg L^?1, and the nitrate (NO₃ ^?)-N to ammonium (NH₄ ⁺)-N ratio was 1:1. Application of excessive Ca began 30 d after sowing (22 d after germination) and continued until 60 d after sowing. From day 60 to day 65 only deionized water, as a leach, was applied. From day 65 to day 90, plants were held under shade cloth and irrigated with tap water. Excessive Ca applied during the production cycle decreased shoot dry weight, shoot fresh weight, leaf number, and shoot tissue K concentration at the end of the production cycle. Excessive Ca applied during the production cycle also decreased shoot dry weight, leaf number, and shoot tissue potassium (K) concentration at the end of the postharvest period. Plant height, plant diameter, number of open flowers, and number of unopened flower buds at the end of the production cycle and at the end of the postharvest period were not affected by the amount of Ca applied during the production cycle. It was concluded that excessive Ca applied to bedding-plant impatiens during the production cycle did not benefit plant performance during either the production cycle or the postharvest period.     

Thermal Structure of Jupiter's Upper Atmosphere Derived from the Galileo Probe

Temperatures in Jupiter's atmosphere derived from Galileo Probe deceleration data increase from 109 kelvin at the 175-millibar level to 900 ± 40 kelvin at 1 nanobar, consistent with Voyager remote sensing data. Wavelike oscillations are present at all levels. Vertical wavelengths are 10 to 25 kilometers in the deep isothermal layer, which extends from 12 to 0.003 millibars. Above the 0.003-millibar level, only 90- to 270- kilometer vertical wavelengths survive, suggesting dissipation of wave energy as the probable source of upper atmosphere heating.