Search NASA⌕ Search

SEARCH · Search NASA

Results for “cotton”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6

Microbiological surface sampling cart

Mobile sampling cart automatically swabs surfaces for the recovery of microorganisms. Unit operates without human involvement and provides for control of swabbing speed, rotation of cotton swab, and the pressure and angle applied to swab. Capability of reverse direction is also available. Sampling cart use is limited to flat surfaces.

Wilkins, J. R.↗

Automatic agar tray inoculation device

Automatic agar tray inoculation device is simple in design and foolproof in operation. It employs either conventional inoculating loop or cotton swab for uniform inoculation of agar media, and it allows technician to carry on with other activities while tray is being inoculated.

Wilkins, J. R.↗

Fourier spectroscopy with a one-million-point transformation

A new type of interferometer for use in Fourier spectroscopy has been devised at the Aime Cotton Laboratory of the National Center for Scientific Research (CNRS), Orsay, France. With this interferometer and newly developed computational techniques, interferograms comprising as many as one million samples can now be transformed. The techniques are described, and examples of spectra of thorium and holmium, derived from one million-point interferograms, are presented.

Connes, J.↗

Reflectance of vegetation, soil, and water

The author has identified the following significant results. A ratio of MSS channels 5 and 7 (5/7) and 5 to 6 (5/6) signals resulted in a correct recognition of 86.9% of the members of representative crop and soil conditions, compared with recognitions of 60.0, 64.1, 74.1, and 81.4% for channels 4, 5, 6, and 7 taken individually. Based on this result a satellite channel ratio procedure has been developed that enhances line printer gray maps for more efficient experimental test site location in the CCT data. Because independent estimates are not available to judge acreage estmates derived from ERTS-1 data against, except for a few crops, an interpenetrating sample constituting 3.5% of the county is ground truthed periodically. The crop of land uses and their acreages, respectively, as estimated from the interpenetrating samples, are: cotton, 129, 714; sorghum, 182,783; mixed citrus, 53,954; oranges, 16,929; grapefruit, 13,863; rangeland, 137,845; and, improved pastures, 57.169.

Wiegand, C. L.↗

A study of the utilization of ERTS-1 data from the Wabash River Basin

The author has identified the following significant results. The crop identification effort produced results indicating difficulty in discriminating cotton and soybeans in the Missouri area in the late August, September-October period. The use of prior probabilities in classification was shown to increase performance significantly. The use of temporal data was observed to improve classification accuracy for September 14 and October 2 data but not for August 26 data. Geometric correction and temporal overlay processing of ERTS-1 data proved to be very valuable for field location and relationship of fields from one time to another. Precision geometric correction of ERTS-1 data was achieved using manually derived ground control checkpoints.

Landgrebe, D. A.↗

Automatic surface inoculation of agar trays.

Description of a machine and technique for the automatic inoculation of a plastic tray containing agar media with a culture, using either a conventional inoculation loop or a cotton swab. The design of the machine is simple, it is easy to use, and it relieves the operator from the manual task of streaking cultures. The described technique makes possible the visualization of the overall qualitative and, to some extent, quantitative relationships of various bacterial types in a sample tested.

Wilkins, J. R.↗

Temporal analysis of multispectral scanner data.

Multispectral scanner reflectance data were sampled for bare soil, cotton, sorghum, corn, and citrus at four dates during a growing season (April, May, June, and July 1969) to develop a time-dependent signature for crop and soil discrimination. Discrimination tests were conducted for single-date and multidate formats using training and test data sets. For classifications containing several crops, the multidate or temporal approach improved discrimination compared with the single-date approach. The multidate approach also preserved recognition accuracy better in going from training fields to test fields than the single-date analysis. The spectral distinctiveness of bare soil versus vegetation resulted in essentially equal discrimination using single-date versus multidate data for those two categories.

Richardson, A. J.↗

Polyurethane retainers for ball bearings

Evaluation of a new ball bearing retainer material is reported. A special composite polyurethane foam ball retainer has been developed that has virtually zero wear, is chemically inert to hydrocarbon lubricants, and stores up to 60 times as much lubricant per unit volume as the most commonly used retainer material, cotton phenolic. This new retainer concept shows promise of years of ball bearing operation without reoiling, based on life testing in high vacuum.

Christy, R. I.↗

Reflectance of vegetation, soil, and water

The author has identified the following significant results. Reflectance of crop residues, that are important in reducing wind and water erosion, was more often different from bare soil in band 4 than in bands 5, 6, or 7. The plant parameters leaf area index, plant population, plant cover, and plant height explained 95.9 percent of the variation in band 7 (reflective infrared) digital counts for cotton and 78.2 percent of the variation in digital counts for the combined crops sorghum and corn; hence, measurable plant parameters explain most of the signal variation recorded for corpland. Leaf area index and plant population are both highly correlated with crop yields; since plant population can be readily measured (or possibly inferred from seeding rates), it is useful measurement for calibrating ERTS-type MSS digital data in terms of yield.

Wiegand, C. L.↗

Reflectance of vegetation, soil, and water

The author has identified the following significant results. The Kubelka-Munk model, a regression model, and a combination of these models were used to extract plant, soil, and shadow reflectance components of vegetated surfaces. The combination model was superior to the others; it explained 86% of the variation in band 5 reflectance of corn and sorghum, and 90% of the variation in band 6 reflectance of cotton. A fractional shadow term substantially increased the proportion of the digital count sum of squares explained when plant parameters alone explained 85% or less of the variation. Overall recognition of 94 agricultural fields using simultaneously acquired aircraft and spacecraft MSS data was 61.8 and 62.8%, respectively; recognition of vegetable fields larger than 10 acres and taller than 25 cm, rose to 88.9 and 100% for aircraft and spacecraft, respectively. Agriculture and rangeland, were well discriminated for the entire county but level 2 categories of vegetables, citrus, and idle cropland, except for citrus, were not.

Wiegand, C. L.↗

Crop identification and acreage measurement utilizing ERTS imagery

The Statistical Reporting Service of the U.S. Department of Agriculture is evaluating ERTS-1 imagery as a potential tool for estimating crop acreage. A main data source for the estimates is obtained by enumerating small land parcels that have been randomly selected from the total U.S. land area. These small parcels are being used as ground observations in this investigation. The test sites are located in Missouri, Kansas, Idaho, and South Dakota. The major crops of interest are wheat, cotton, corn, soybeans, sugar beets, potatoes, oats, alfalfa, and grain sorghum. Some of the crops are unique to a given site while others are common in two or three states. This provides an opportunity to observe crops grown under different conditions. Results for the Missouri test site are presented. Results of temporal overlays, unequal prior probabilities, and sample classifiers are discussed. The amount of improvement that each technique contributes is shown in terms of overall performance. The results show that useful information for making crop acreage estimates can be obtained from ERTS-1 data.

Wigton, W. H.↗

Apparatus for microbiological sampling

An automatic apparatus is described for microbiologically sampling surface using a cotton swab which eliminates human error. The apparatus includes a self-powered transport device, such as a motor-driven wheeled cart, which mounts a swabbing motor drive for a crank arm which supports a swab in the free end thereof. The swabbing motor is pivotably mounted and an actuator rod movable responsive to the cart traveling a predetermined distance provides lifting of the swab from the surface being sampled and reversal of the direction of travel of the cart.

Wilkins, J. R.↗

Automatic inoculating apparatus

An automatic inoculating apparatus for agar trays is described and using a simple inoculating element, such as a cotton swab or inoculating loop. The apparatus includes a movable carriage for supporting the tray to be inoculated, a drive motor for moving the tray along a trackway, and a swabbing motor for automatically swabbing the tray during the movement. An actuator motor controls lowering of the inoculating element onto the tray and lifting of the inoculating element. An electrical control system, including limit microswitches, enables automatic control of the actuator motor and return of the carriage to the initial position after inoculating is completed.

Wilkins, J. R.↗

Synthesis and evaluation of polymers for use in early warning fire alarm devices

Conjugated polyacetylene polymers and one condensation polyene, all containing a high degree of conjugated unsaturation, were synthesized. These polymers were characterized by chemical analysis and by thermogravimetric analysis, as well as for their film-forming capability and gas/polymer interactions. It was found that those that had a high degree of conjugated unsaturation and had resonance - stabilizing groups were very thermally stable to 200 C, e.g., poly(dicyanoacetylene), poly(ethynylferrocene) and poly(phenylacetylene); while those with labile moieties, such as poly(p-formamidophenylacetylene), among others, suffered some degradation when heated in air. When subjected to gas/polymer interaction effects, the greatest change in electrical conductance was observed when ammonia was used as the gas and poly(p-nitrophenylacetylene) was the detector. Other polymers showed similar behavior. For example, poly(ethynylcarborane), considered to be an electron acceptor also showed a change in electrical conductance when exposed to ammonia, while poly(ethynylpyridine) and poly(ethylidenepyridazine) responded to carbon monoxide. However, for "fire gases" (gases from smoldering cotton), poly(ethynylferrocene) was the most responsive. Thus, the concept of polymers with different electronegativities forming charge-transfer complexes with different gases was found to be operable.

Byrd, N. R.↗

Reflectance of vegetation, soil, and water

The author has identified the following significant results. Bands 4, 5, and 7 and 5, 6, and 7 were best for distinguishing among crop and soil categories in ERTS-1 SCENES 1182-16322 (1-21-73) and 1308-16323 (5-21-73) respectively. Chlorotic sorghum areas 2.8 acres or larger in size were identified on a computer printout of band 5 data. Reflectance of crop residues was more often different from bare soil in band 4 than in bands 5, 6, and 7. Simultaneously acquired aircraft and spacecraft MSS data indicated that spacecraft surveys are as reliable as aircraft surveys. ERTS-1 data were successfully used to estimate acreage of citrus, cotton, and sorghum as well as idle crop land.

Wiegand, C. L.↗

Controlled generation of large volumes of atmospheric clouds in a ground-based environmental chamber

Atmospheric clouds were generated in a 23,000 cubic meter environmental chamber as the first step in a two part study on the effects of contaminants on cloud formation. The generation procedure was modeled on the terrestrial generation mechanism so that naturally occurring microphysics mechanisms were operative in the cloud generation process. Temperature, altitude, liquid water content, and convective updraft velocity could be selected independently over the range of terrestrially realizable clouds. To provide cloud stability, a cotton muslin cylinder 29.3 meters in diameter and 24.2 meters high was erected within the chamber and continuously wetted with water at precisely the same temperature as the cloud. The improved instrumentation which permitted fast, precise, and continual measurements of cloud temperature and liquid water content is described.

Hettel, H. J.↗

Further tests of plant canopy reflectance models and investigation of non-Lambertian properties of plant canopies

The experimental bidirectional reflectance of cotton is presented and compared to the Suits vegetation model. Some wheat reflectance data are presented for a Mexican dwarf wheat. The general results are that the exchange of source position and detector position gives the same reflectance measurement if the irradiance is purely specular. This agrees with Suites. The reflectance versus sun angle and reflectance versus detector angle do not agree with the Suits predictions. There is qualitative agreement between the Suits model and reflectance versus wavelength, but quantitative agreement has not been observed. Reflectance of a vegetation canopy with detector azimuth shows a change of 10 to 40% for even sun angles near zenith, so it seems advisable to include azimuthal angles into models of vegetation.

Lemaster, E. W.↗