GROW1: a crop growth model for assessing impacts of gaseous pollutants from geothermal technologies (open access)

GROW1: a crop growth model for assessing impacts of gaseous pollutants from geothermal technologies

A preliminary model of photosynthesis and growth of field crops was developed to assess the effects of gaseous pollutants, particularly airborne sulfur compounds, resulting from energy production from geothermal resources. The model simulates photosynthesis as a function of such variables as irradiance, CO/sub 2/ diffusion resistances, and internal biochemical processes. The model allocates the products of photosynthesis to structural (leaf, stem, root, and fruit) and storage compartments of the plant. The simulations encompass the entire growing season from germination to senescence. The model is described conceptually and mathematically and examples of model output are provided for various levels of pollutant stress. Also, future developments that would improve this preliminary model are outlined and its applications are discussed.
Date: March 17, 1977
Creator: Kercher, J.R.
System: The UNT Digital Library
The acute radiation syndrome: A study of ten cases and a review of the problem (open access)

The acute radiation syndrome: A study of ten cases and a review of the problem

In this report ten cases of acute radiation syndrome are described resulting from two accidents occurring at the Los Alamos Scientific Laboratory of unique nature involving fissionable material. These cases are described in considerable detail. The report comprises ten sections. This volume, part II of the report, is comprised of sections entitled: (1) the Biological Basis for the Clinical Response seen in the Acute radiation Syndrome, (2) Clinical Signs and Symptoms, (3) Discussion of Hematological Findings, (4) Chemistry of the Blood and Urine, (5) Discussion of Pathological Findings, and (6) Reconsiderations of the Calculated Radiation Doses in Terms of the Observed Biological Response of the Patients. This report was prepared primarily for the clinician who is interested in radiation injuries and therefore emphasis has been placed on the correlation of clinical and pathological changes with the type of cytogenetic change known to be produced by ionizing radiation.
Date: March 17, 1950
Creator: Hempelmann, L.H. & Lisco, H.
System: The UNT Digital Library
Principles of X-ray Navigation (open access)

Principles of X-ray Navigation

X-ray navigation is a new concept in satellite navigation in which orientation, position and time are measured by observing stellar emissions in x-ray wavelengths. X-ray navigation offers the opportunity for a single instrument to be used to measure these parameters autonomously. Furthermore, this concept is not limited to missions in close proximity to the earth. X-ray navigation can be used on a variety of missions from satellites in low earth orbit to spacecraft on interplanetary missions. In 1997 the Unconventional Stellar Aspect Experiment (USA) will be launched as part of the Advanced Research and Global Observation Satellite (ARGOS). USA will provide the first platform for real-time experimentation in the field of x-ray navigation and also serves as an excellent case study for the design and manufacturing of space qualified systems in small, autonomous groups. Current techniques for determining the orientation of a satellite rely on observations of the earth, sun and stars in infrared, visible or ultraviolet wavelengths. It is possible to use x-ray imaging devices to provide arcsecond level measurement of attitude based on star patterns in the x-ray sky. This technique is explored with a simple simulation. Collimated x-ray detectors can be used on spinning satellites to provide …
Date: March 17, 2006
Creator: Hanson, John Eric
System: The UNT Digital Library