The reactivity of aluminosilicate glasses in cements - effects of Ca content on dissolution characteristics and surface precipitation

Non peer reviewedPostprin

Reliability study of the NiH2 strain gage

This paper summarizes a joint study by Gates Aerospace Batteries (GAB) and the Reliability Analysis Center (RAC). This study characterizes the reliability and robustness of the temperature compensated strain gages currently specified for sensing of internal pressure of NiH2 cells. These strain gages are characterized as fully encapsulated, metallic foil grids with known resistance that varies with deformation. The measurable deformation, when typically installed on the hemispherical portion of a NiH2 cell, is proportional to the material stresses as generated by internal cell pressures. The internal pressure sensed in this manner is calibrated to indicate the state-of-charge for the cell. This study analyzes and assesses both robustness and reliability for the basic design of the strain gage, the installation of the strain gage, and the circuitry involved

ECONOMICS OF ALTERNATIVE BEEF CATTLE GENOTYPE AND MANAGEMENT/MARKETING SYSTEMS

Livestock Production/Industries,

THE DEMAND FOR WHOLESALE BEEF CUTS BY SEASON AND TREND

This study estimates demand during the 1980-90 period for wholesale beef cuts by season and by trend. A data set containing monthly nominal prices for wholesale cuts and average choice boxed beef from January 1980 to December 1990 was collected from multiple sources. The approach expressed the change in demand for wholesale cuts as the change in the price ratio of individual cuts relative to the price of boxed beef. This approach shows changes in amount by season and over time relative to the average wholesale cut. Brisket, Armbone Chuck, Bottom Gooseneck, and Knuckle showed the strongest demand in winter and lowest in summer. Top (Inside) Round had a clear downward trend in demand, but the seasonal pattern was less pronounced and more erratic than the lower-priced cuts. Top Sirloin Butt had its highest demand in spring and summer with November-December being the lowest period. Strip Loin had the strongest warm season demand during the period which contains Memorial Day. Ribeye experienced a seasonal demand highest in November-December and lowest in January to April. Full Tenderloin was the most expensive wholesale beef cut analyzed in the study, and its demand was highest in November-December. The study clearly showed that a change in seasonal demand was responsible for the major part of price ratio fluctuations for individual wholesale cuts.Demand and Price Analysis,

Instruções para o cultivo do coqueiro anão.

bitstream/item/26595/1/F-cultivo-coqueiro-anao.pd

Radiological assessment for Space Station Freedom

Circumstances have made it necessary to reassess the risks to Space Station Freedom crewmembers that arise from exposure to the space radiation environment. An option is being considered to place it in an orbit similar to that of the Russian Mir space station. This means it would be in a 51.6 deg inclination orbit instead of the previously planned 28.5 deg inclination orbit. A broad range of altitudes is still being considered, although the baseline is a 407 km orbit. In addition, recent data from the Japanese A-bomb survivors has made it necessary for NASA to have the exposure limits reviewed. Preliminary findings of the National Council on Radiation Protection and Measurements indicate that the limits must be significantly reduced. Finally, the Space Station will be a laboratory where effects of long-term zero gravity on human physiology will be studied in detail. It is possible that a few crewmembers will be assigned to as many as three 1-year missions. Thus, their accumulated exposure will exceed 1,000 days. Results of this radiation risk assessment for Space Station Freedom crewmembers finds that females less than 35 years old will be confined to mission assignments where the altitude is less than about 400 km. Slight restrictions may also need to be made for male crewmembers less than 35 years old

50 Years of Spaceflight with Fourier Transform Spectrometers (FTS) Built at NASA GSFC

Over the past 50 years, NASA Goddard Space Flight Center (GSFC) has been developing, building, testing and flying a series of Fourier Transform Spectrometers (FTS). This began with the IRIS instruments on the Earth-orbiting Nimbus satellites and progressed to more sophisticated designs optimized for interplanetary spacecraft sent to Mars and later to the outer solar system. Adaptions have been made over time, including progressively higher spectral resolution, sensitivity, numbers of detectors and complexity. Instrument operating temperatures have decreased to enable remote sensing of the cold giant planet systems. In this paper we describe the historical evolution of this instrument line, comparing and contrasting different aspects such as optical design and materials, detector types and data handling. We conclude by looking towards the future. At present the CIRS-Lite prototype is being tested at NASA GSFC for potential use on a future mission to the ice giants, Uranus and Neptune. Surpassing the previous performance of the Voyager IRIS instruments remains challenging, and new technologies that could enable these measurements are discussed