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Resource capture by single leaves

Description: Leaves show a variety of strategies for maximizing CO{sub 2} and light capture. These are more meaningfully explained if they are considered in the context of maximizing capture relative to the utilization of water, nutrients and carbohydrates reserves. There is considerable variation between crops in their efficiency of CO{sub 2} and light capture at the leaf level. Understanding of these mechanisms indicate some ways in which efficiency of resource capture could be level cannot be meaningfull… more
Date: May 1, 1992
Creator: Long, S.P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The bioenergetics of salt tolerance

Description: The aim of this project was to try to understand the adaptive mechanisms that organisms develop in order to respond to a sudden transformation in their environment to a salt shock.'' To study this problem we used a fresh water oxygenic photosynthetic cyanobacterium known as Synecoccus 6311. This organism suffers injury after this sudden exposure to high concentrations of sodium chloride equivalent to or even higher than that in sea water. Yet they are able to re-establish their photosynthetic a… more
Date: January 1, 1991
Creator: Packer, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effects of energy related activities on the plankton of the Chesapeake Bay. Section 1. Progress report, 1 August 1976--30 September 1977

Description: Progress is reported on a comprehensive study of the ecology of the Chesapeake Bay estuary system. Emphasis is placed on seasonal variations of initial energy fixation by phytoplankton primary producers and subsequent energy transfer to herbivours and becterial heterotrophs. The impact of chemical and radioactive effluents from electric power plants on the ecology of Chesapeake Bay will be assessed. Data are included on the role of plankton metabolism in regenerating nutrients, nutrient exchang… more
Date: 1977~
Creator: Taft, Jay L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cationically polymerizable monomers derived from renewable sources

Description: The objective of this project is to make use of products obtained from renewable plant sources as monomers for the direct production of polymers which can be used for a wide range of plastic applications. In this report is described progress in the synthesis and polymerization of cationically polymerizable monomers and oligomers derived from botanical oils, terpenes, natural rubber, and lignin. Nine different botanical oils were obtained from various sources, characterized and then epoxidized. … more
Date: October 1, 1991
Creator: Crivello, J. V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Photodegradation of mutagens in solvent-refined coal liquids

Description: The purpose of this investigation was to evaluate any changes in the chemical composition and microbial mutagenicities of two representative solvent-refined coal (SRC) liquids as a function of exposure time to sunlight and air. This information was desired to assess potential health hazards arising from ground spills of these liquids during production, transport and use. Results of microbial mutagenicity assays using Salmonella typhimurium TA98, conducted after exposure, showed that the mutagen… more
Date: April 1, 1984
Creator: Kalkwarf, D. R.; Stewart, D. L.; Pelroy, R. A. & Weimer, W. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dynamics of H sub 2 elimination from unsaturated hydrocarbons

Description: State-of-the-art laser and molecular beam techniques are used to study the dynamics of H{sub 2} elimination from 1,4-cyclohexadiene and ethylene. Information on the transition state configurations and the dynamics of the dissociation processes for these reactions is reported. 152 refs., 54 figs., 12 tabs.
Date: February 1, 1991
Creator: Cromwell, E.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Photoproduction of hydrogen by membranes of green photosynthetic bacteria

Description: Photoproduction of H/sub 2/ from ascorbate by unit-membrane vesicles from Chlorobium limicola f. thiosulfatophilum was achieved with a system containing gramicidin D, tetramethyl-p-phenylenediamine, methyl viologen, dithioerythritol, Clostridium hydrogenase, and an oxygen-scavenging mixture of glucose, glucose oxidase, ethanol, and catalase. Maximum quantum yield was less than one percent. Half maximum rate of H/sub 2/ production occurred at a white-light intensity of approximately 0.15 cm/sup … more
Date: January 1, 1980
Creator: Bernstein, J D & Olson, J M
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Excited-state proton-transfer kinetics in 1-naphthol, 1-naphthol-sulfonates, and organometallic complexes

Description: The dissociation of 1-naphthol in aqueous solution occurs so rapidly that the fluorescence from the neutral form, ROH, has been previously described as completely extinguished or hardly noticeable. Apparently nearly all of the fluorescence originates from the naphtholate ion. This paper reports on the proton-transfer characteristics of a series of 1-naphthol compounds, and also reports preliminary data on excited-state proton transfer in an organometallic complex of ruthenium.
Date: July 1, 1980
Creator: Shapiro, S. L.; Winn, K. R. & Clark, J. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Experimental investigation of the chemistry of excited states of rare gases. First quarterly progress report, October 15, 1977--January 15, 1978

Description: The quenching of XeF(B) was studied using the steady-state photolysis of XeF/sub 2/ as the source of XeF(B). The product states from the sensitized reaction of Xe(/sup 3/P/sub 1/) with Cl/sub 2/ and COCl/sub 2/ also were studied. The new XeF(B) quenching rate constants are described. The pulsed laser induced fluorescence technique was used to measure radiative lifetimes and two-body quenching rate constant (with Ar) for the low energy Xe(6p)* states. Serious signal/noise problems for the lowest… more
Date: February 1978
Creator: Setser, D. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Walker Branch Watershed: site description and research scope

Description: Walker Branch Watershed is located on the Oak Ridge Reservation in the Ridge and Valley section of Tennessee. The watershed (97 ha consisting of 2 subwatersheds) is underlain by Knox Dolomite; soils formed over the dolomitic substrate are deep, well-drained Typic Paleudults. The watershed is forested. The overstory is predominantly oak-hickory with lesser amounts of pine and mesic hardwoods. The Walker Branch Watershed Project was initiated in 1967 to: relate the productivity and water quality … more
Date: January 1, 1977
Creator: Harris, W. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Studies of air pollution effects on vegetation

Description: The report consists of three parts which summarize pollutant-vegetation effects research studies. These include: oxidant effects of primary productivity in ponderosa pine in the San Bernardino National Forest; air pollution effects on vegetation related to geothermal power development; and regional assessment of air pollution impact on vegetation by mathematical modeling. A list of publications that report results of the studies is included in an appendix.
Date: January 1, 1978
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Life sciences

Description: This document is the 1989--1990 Annual Report for the Life Sciences Divisions of the University of California/Lawrence Berkeley Laboratory. Specific progress reports are included for the Cell and Molecular Biology Division, the Research Medicine and Radiation Biophysics Division (including the Advanced Light Source Life Sciences Center), and the Chemical Biodynamics Division. 450 refs., 46 figs. (MHB)
Date: April 1, 1991
Creator: Day, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Energetic control of intact chloroplast photosynthesis

Description: The induction phase of photosynthesis was studied in intact chloroplasts isolated from spinach. Within 15 sec of illumination, stromal ADP is phosphorylated to give an ATP/ADP ratio of 1.4. A transthylakoid pH gradient of about 4.1 units developed during the first min, and was associated with a low note of linear electron flow from H/sub 2/O to NADP/sup +/. In the following 2 to 3 min, both the pH gradient and ATP/ADP ratio declined to new steady state levels (3.9 pH units and a ratio of 0.9), … more
Date: unknown
Creator: Slovacek, R E & Hind, G
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Vectorially photoinduced electron-transfer processes across water-in-oil interfaces of microemulsions

Description: Artificial photosynthetic devices are potential fuel sources. The basic idea in the design of such devices is a photosensitized electron-transfer that yields chemical species capable of reducing and oxidizing water to hydrogen and oxygen. A fundamental difficulty in effecting this transfer is the thermodynamically favored back reactions of the intermediary redox species. An interfacial model composed of a water-in-oil microemulsion is suggested to provide the separation of these redox species, … more
Date: July 1, 1980
Creator: Willner, I.; Otvos, J. W. & Calvin, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Hydrogen-Transfer and Charge Transfer in Photochemical and High Energy Radiation Induced Reactions: Effects of Thiols. Final Report, February 1, 1960-January 31, 1979

Description: Absorption of ultraviolet or visible light, or high energy radiation, may lead to highly reactive free radicals. Thiols affect the reactions of these radicals in the following ways: (1) transfer of hydrogen from sulfur of the thiol to a substrate radical, converting the radical to a stable molecule, and the thiol to a reactive thiyl radical; and (2) transfer of hydrogen from a substrate radical or molecule to thiyl, regenerating thiol. The thiol is thus used repeatedly and a single molecule may… more
Date: March 1, 1980
Creator: Cohen, S. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Solar-collector-materials exposure to the IPH site environment. Volume 1. Final report

Description: In-situ environmental exposure tests were conducted at nine proposed intermediate-temperature Industrial Process Heat (IPH) sites. Three types of reflector materials were evaluated for survivability at the nine sites: second-surface silvered glass, aluminized acrylic FEK-244 film on aluminumsubstrate and Alzak (electropolished aluminum) on aluminium substrate. Black chrome absorber material and low-iron float glass were evaluated for thermal, photochemical, and environmental degradation. The re… more
Date: January 1, 1982
Creator: Morris, V.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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(Structure and function in photosynthetic membranes and their components). Annual progress report, December 1, 1978-November 30, 1979

Description: Structure and function are being studied in photosynthetic membranes and their components, principally with Rhodopseudomonas sphaeroides. That bacteriochlorophyll (Bchl) can have a strongly shifted absorption maximum in the membrane, without the involvement of excitonic Bchl-Bchl interactions was demonstrated. The orientations of pigments in the membrane are being determined, and the orientations of four distinguishable carotenoid components are under investigation. These studies provide data f… more
Date: January 1, 1979
Creator: Clayton, R.K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Long-term durability of polyethylene for encapsulation of low-level radioactive, hazardous, and mixed wastes

Description: The durability of polyethylene waste forms for treatment of low-level radioactive, hazardous, and mixed wastes is examined. Specific potential failure mechanisms investigated include biodegradation, radiation, chemical attack, flammability, environmental stress cracking, and photodegradation. These data are supported by results from waste form performance testing including compressive yield strength, water immersion, thermal cycling, leachability of radioactive and hazardous species, irradiatio… more
Date: January 1, 1991
Creator: Kalb, P. D.; Heiser, J. H. & Colombo, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A kinetics study of the O( sup 3 P) + CH sub 3 Cl reaction over the 556-1485 K range by the HTP and LP-ST techniques

Description: The high-temperature photochemistry (HTP) and laser photolysis-shock tube (LP-ST) techniques have been combined to study the kinetics of the reaction between ground-state oxygen atoms with CH{sub 3}Cl over the temperature range, 556--1485 K. In the HTP reactor, used for the 556--1291 K range, O atoms were generated by flash photolysis of O{sub 2}, CO{sub 2} or SO{sub 2}, and the atom concentrations were monitored by resonance fluorescence, while with the LP-ST technique, used for the 916--1485 … more
Date: December 1, 1991
Creator: Ko, Taeho; Fontijn, A. (Rensselaer Polytechnic Inst., Troy, NY (United States). High-Temperature Reaction Kinetics Lab.); Lim, K.P. & Michael, J.V. (Argonne National Lab., IL (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Combustion Research Program: Flame studies, laser diagnostics, and chemical kinetics

Description: We have made a detailed study of the care that must be taken to correctly measure OH radical concentrations in flames. A large part of these studies has concerned collisional quenching of hydride radical species (OH, NH, and NH{sub 2}), in particular the dependence upon rotational level and collision velocity (temperature). The results on OH and NH have shown unique and interesting behavior from the viewpoint of fundamental molecular dynamics, pointing to quenching often governed by collisions … more
Date: January 22, 1991
Creator: Crosley, D.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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