1,696 research outputs found
Viking Orbiter completion mission and Viking Lander monitor mission
A brief history of the Viking Missions is presented. The status of the present Viking Orbiter and Landers for the period from February 1, 1980 through March 31, 1980 is discussed, with emphasis on data transmission abilities
Plasma cleaning device
High vacuum cleaning of contaminated surfaces such as hydrocarbon containment films can be accomplished by a plasma cleaning device which includes a plasma discharge housing to permit generation of a plasma in an environment having a higher pressure than the surface which is to be cleaned. A ground electrode and a radio frequency electrode partially surround a quartz plasma tube, for the introduction of an ionizable gas. These electrodes ionize the gas and help generate the plasma. This plasma flows through a non-constrictive aperture, through the plasma discharge housing and then on to the contaminated surface
Laboratory demonstration model: Active cleaning technique device
The technique which utilizes exposure to a plasma to remove contaminants from a surface was incorporated into a laboratory model which demonstrates active cleaning by both plasma cleaning and ion sputtering modes of operation. The development phase is reported and includes discussion of the plasma tube configuration, device design, and performance tests. A general description of the active cleaning device is provided which includes information on the main power/plasma discharge sensors, and the power, gas supply, and ion accelerator systems. Development of the active cleaning species at high vacuum conditions is described and results indicate that plasma cleaning occurs in the region of a visible plume which extends from the end of the plasma tube. Recommendations are made for research to determine the plasma cleaning mechanism and the plasma species responsible for the cleaning, as well limitations on the type of contaminants that can be removed
Active cleaning technique for removing contamination from optical surfaces in space
An active cleaning technique for removing contaminants from optical surfaces in space was investigated with emphasis on the feasibility of using plasma exposure as a means of in-situ cleaning. The major work accomplished includes: (1) development of an in-situ reflectometer for use in conjunction with the contaminant film deposition/cleaning facility; (2) completion of Apollo Telescope Mount (ATM) filter treatment experiments to assess the effects of plasma exposure on the UV transmittance; (3) attempts to correlate the atomic oxygen flux with cleaning rate; (4) completion of in-situ butadien contamination/plasma cleaning/UV reflectance measurement experiments; (5) carbon cleaning experiments using various gases; (6) completion of silicone contamination/cleaning experiments; and (7) experiments conducted at low chamber pressures to determine cleaning rate distribution and contamination of surfaces adjacent to those being cleaned
Evaluation of Foam Fractionation Column Scale-Up for Recovering Bovine Serum Albumin
Foam fractionation is an adsorptive-bubble separation method that, according to researchers, is a feasible technique for the separation and/or concentration of proteins. The foam fractionation of bovine serum albumin (BSA) in laboratory-scale foam fractionation columns (750 and 1250 mL) and the relationship between the two laboratory-scale columns and a pilot-scale column (5000 mL) were investigated. Recovery, enrichment, and performance factor values were experimentally determined with three different column volumes with varying pore sizes, gas superficial velocities, and, in the case of the 750 mL column, foam column height. As the pore size decreased, the amount of protein recovered from the dilute protein solution increased and the enrichment decreased. As the flow rate of the gas increased, the effect of the pore size decreased. For the three column volumes, the optimal column conditions were achieved with the largest pore size (145-174 μm) and an intermediate superficial gas velocity (7 mm/s). Increasing the foam column height increased the enrichment without sacrificing the recovery of the target protein. In the case of the largest pore size, the linear relationships between the recovery and the ratio of gas volume to initial liquid volume are parallel, such that the recovery in a pilot-scale column (5000 mL) can be predicted with the recovery found with a laboratory-scale column (750 or 1250 mL)
Upper-surface blowing nacelle design study for a swept wing airplane at cruise conditions
A study was made to design two types of overwing nacelles for an existing wing-body at a design condition of Mach = 0.8 and C sub L = 0.2. Internal and external surface contours were developed for nacelles having either a D-shaped nozzle or a high-aspect-ratio nozzle for upper-surface blowing in the powered-lift mode of operation. The goal of the design was the development of external nacelle lines that would minimize high-speed aerodynamic interference effects. Each nacelle type was designed for both two- and four-engine airplanes using an iterative process of aerodynamic potential flow analysis. Incremental nacelle drag estimates were made for flow-through wind tunnel models of each configuration
New County Record For The Veiled Chameleon, Chamaeleo calyptratus Duméril and Bibron 1851 (Sauria: Chamaeleonidae), in Florida
The Milch Goat
Interest in the milch goat has been stimulated by the world-wide food shortage and a keener appreciation of the food value of milk. Altho goats are kept mainly for the production of mohair, meat and hides, several milk-producing strains are recognized and in some countries a large percentage of the milk produced Is goat\u27s milk. Germany had at the beginning of the war about 4,000,000 milk producing goats which returned annually over three times their capitalized value in the form of milk and by-products. While goats are widely known as scavengers, they must be fed liberally and well managed to secure the highest production. Goats\u27 milk, tho ill adapted for butter making, is excellent for cheese making and !or Infants and invalids. Its apparent freedom from tuberculosis also enhances Its value for these purposes. Goats are not, however, as economical dairy animals as cows, requiring over three and a half times as much feed per quart of milk produced. Care should be exercised by purchasers of goats to secure animals adapted for milk production
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