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Recolonization of reactor cooling water system by the Asiatic clam Corbicula fluminea

Description: Recolonization rates for the Asiatic clam Corbicula fluminea ranged from 3.0 to 5.6 metric tons per year in cooling water basins for a nuclear production reactor at the Savannah River Plant. However, a 10-month cleaning cycle for each basin (flow area, 6100 m/sup 2/) keeps the depth of the silt/clam layer low. With this cleaning frequency, Corbicula are not reaching heat exchangers at sufficient size or in sufficient numbers to restrict flow. Data are presented on the size/age distribution for clams recolonizing cooling water basins between cleanings.
Date: January 1, 1978
Creator: Harvey, R.S.
Partner: UNT Libraries Government Documents Department

The World Food Conference: Implications for Congressional Action

Description: This report discusses the World Food Conference held in Rome, Italy in November 1974 which was organized by the UN to address food shortages, international hunger relief, and improved food production methods. Major recommendation of the conference and possible Congressional action related to these recommendations are discussed.
Date: December 8, 1974
Creator: Sherman, Harvey R.
Partner: UNT Libraries Government Documents Department

Advanced Thermoelectric Power System. Final Report

Description: Development of a radioisotope-fueled thermoelectric power-conversion system for the SNAP program is discussed. The generator operates at somewhat less than 1% over-all efficiency, has a power output of approximately 1.45 watts, and has a specific power of 0.l42 watts per pound. The power-flattening device did not perform as expected. A second generator is also described which produces a maximum power of 1.6 watts, has a maximum efficiency of 1.20%, and has a specific power of 0.32 watts per pound (exclusive of the weight of the heat source). (auth)
Date: January 1, 1960
Creator: Harvey, R. J.
Partner: UNT Libraries Government Documents Department

Temperature Effect on the Sorption of Radionuclides by Freshwater Algae

Description: The heavy waters of the reactor effluent streams within the Savannah River Plant area transport very low concentrations of fission and activation products through miles of natural streambeds and swamps to the Savannah River. This study emphasizes the effects of environmental factors on the sorption of radionuclides by representative species.
Date: January 6, 2003
Creator: Harvey, R.S.
Partner: UNT Libraries Government Documents Department

Effect of Dead Algae on Soil Permeability

Description: Since existing basins support heavy growths of unicellular green algae which may be killed by temperature variation or by inadvertent pH changes in waste and then deposited on the basin floor, information on the effects of dead algae on soil permeability was needed. This study was designed to show the effects of successive algal kills on the permeability of laboratory soil columns.
Date: February 21, 2003
Creator: Harvey, R.S.
Partner: UNT Libraries Government Documents Department

Effectiveness of bromicide against Legionella pneumophila in a cooling tower

Description: Cooling towers are considered to be man-made amplifiers of Legionella. Thus the proper maintenance and choice of biocides is important. The only biocide that has thus far been shown to be effective in field tests is the judicious use of chlorination. Perturbation studies were conducted on an industrial cooling tower shown to contain Legionella, using 1-bromo-3-chloro-5,5-dimethylhydantoin (Bromicide, Great Lakes Chemical Corp.). At the manufacturer's recommended concentrations neither the density nor the activity of Legionella was affected. At concentrations greater than 2.0 ppM free residual, the Bromicide was not effective in reducing Legionella to source water concentrations, nor was it effective in reducing the INT activity of the bacterium in situ. The data indicate that at concentrations up to 2.0 ppM, Bromicide is not effective in these tower studies. 23 references, 3 tables.
Date: January 1, 1983
Creator: Fliermans, C.B. & Harvey, R.S.
Partner: UNT Libraries Government Documents Department

Effects of anomalous transport on lower hybrid electron heating

Description: The transport of electron energy out of tokamaks is known to be far greater than that calculated using classical and neoclassical theory. However, low levels of non-axisymmetric magnetic field turbulence can couple the fast transport of electrons parallel to the magnetic field lines to radial transport, thus providing a plausible explanation for observed energy confinement. These models further predict that the electron loss rate is proportional to v/sub parallel bars/. This has subsequently been found to be consistent with data for runaway electrons in PLT, at energies up to 1 MeV. Recently it has been pointed out by Chan, Chiu and Ohkawa that anomalous transport processes should be taken into account in attempting to determine steady state electron distribution functions for cases involving RF electron tail heating, particularly in view of the v/sub parallel bars/ dependence of the loss rate. In this work these physical processes are modeled through a 2-D nonlinear program which describes the evolution of the electron distribution function in velocity magnitude; (v) and plasma radius (r), and which studies the efficiency of tail electron heating.
Date: February 1, 1981
Creator: McCoy, M.G. & Harvey, R.W.
Partner: UNT Libraries Government Documents Department

Life history, development processes, and energetics of the burrowing mayfly

Description: Dolania americana Edmunds and Traver is a burrowing mayfly known only from three coastal plain streams in the southeastern United States. In Upper Three Runs, a spring-fed blackwater stream in South Carolina, D. americana is the dominant mayfly species inhabiting the sandy substrate. Larvae are very distinct morphologically, being highly adapted for burrowing in sandy substrate. D. americana are predators and feed mainly on midge larvae. This paper describes quantitatively: (1) the bioenergetics and developmental dynamics of the larval stage; (2) adult emergence and fecundity; and (3) biochemical characteristics of the eggs. These data are used to delineate both the life history of D. americana and the overall importance of this species to energy flow in Upper Three Runs.
Date: January 1, 1979
Creator: Harvey, R.S.; Vannote, R.L. & Sweeney, B.W.
Partner: UNT Libraries Government Documents Department

SNAP Programs. Quarterly Progress Report No. 4 for July 1 through September 30, 1960. Subtask 5.3 and Task 6

Description: Generator 2A the design of which was completed last quarter, was fabricated and electrically tested. The generator met all significant design requirements with the exception of the collector work function. During the preparations for environmental tests one of the leadthroughs falled. Metallographic examination revealed that it is necessary to make some design revisions of the leadthrough. Generator 2A was an experimental unit which led to the design of generator 2B. Specifically, the conclusions obtained from 2A confirmed certain processing methods applicable to future units. The latter unit includes provisions for remote control fueling, and its operation should attain anticipated performance characteristics (P/sub o/, w, T/sub e/, T/sub c/ and life). Critical areas of design, construction, and processing of 2B include the facillty for remote control fueling, the attainment of close interelectrode spacing and low collector work function, and the achievement of a rugged genenator. Accordingly, a vigorous theoretical and experimental approach was undertaken. A life test on generator lA was initiated and over 2100 hr of operating time was accumulated. The emitter was not aged prior to incorporation into the generator; as a result, the evaporation of barium from the emitter eventually reduced the diode internal resistance to the point where it was no longer feasible to continue the life test. The procedures for fueling a thermionic generator with a Cm/sup 242/ heat source were established. An activation device in which a work function of approximately 1.9 volts was achieved was designed, fabricated, and tested. These same techniques can be incorporated in a practical generator design. Following this test, the preliminary design of generator 2B was established, and development on the design was initiated. To date, considerable progress has been made in the development of purification processes for gram quantities of americium and curium. Design, fabrication, and installation of experimental ...
Date: October 31, 1961
Creator: Harvey, R. & Bowes, W. M.
Partner: UNT Libraries Government Documents Department

Three-dimensional simulations of electron cyclotron heating

Description: Many heating problems in tokamaks are inherently three dimensional, involving the velocity coordinates parallel and perpendicular to the ambient magnetic field and the plasma radial coordinate. We will describe a new three-dimensional, Fokker-Planck/rf quasilinear code. This code is based upon a two-dimensional in velocity space Fokker-Planck code which solves for the distribution evaluated at the outer equatorial plane (theta = 0) of each flux surface in a radial mesh.
Date: August 1, 1985
Creator: McCoy, M.G.; Kerbel, G.D. & Harvey, R.W.
Partner: UNT Libraries Government Documents Department

Revisiting the Cape Cod Bacteria Injection Experiment Using a Stochastic Modeling Approach

Description: Bromide and resting-cell bacteria tracer tests carried out in a sand and gravel aquifer at the USGS Cape Cod site in 1987 were reinterpreted using a three-dimensional stochastic approach and Lagrangian particle tracking numerical methods. Bacteria transport was strongly coupled to colloid filtration through functional dependence of local-scale colloid transport parameters on hydraulic conductivity and seepage velocity in a stochastic advection-dispersion/attachment-detachment model. Information on geostatistical characterization of the hydraulic conductivity (K) field from a nearby plot was utilized as input that was unavailable when the original analysis was carried out. A finite difference model for groundwater flow and a particle-tracking model of conservative solute transport was calibrated to the bromide-tracer breakthrough data using the aforementioned geostatistical parameters. An optimization routine was utilized to adjust the mean and variance of the lnK field over 100 realizations such that a best fit of a simulated, average bromide breakthrough curve is achieved. Once the optimal bromide fit was accomplished (based on adjusting the lnK statistical parameters in unconditional simulations), a stochastic particle-tracking model for the bacteria was run without adjustments to the local-scale colloid transport parameters. Good predictions of the mean bacteria breakthrough data were achieved using several approaches for modeling components of the system. Simulations incorporating the recent Tufenkji and Elimelech [1] equation for estimating single collector efficiency were compared to those using the Rajagopalan and Tien [2] model. Both appeared to work equally well at predicting mean bacteria breakthrough using a constant mean bacteria diameter for this set of field conditions, with the Rajagopalan and Tien model yielding approximately a 30% lower peak concentration and less tailing than the Tufenkji and Elimelech formulation. Simulations using a distribution of bacterial cell diameters available from original field notes yielded a slight improvement in the model and data agreement compared to simulations using an ...
Date: November 22, 2006
Creator: Maxwell, R M; Welty, C & Harvey, R W
Partner: UNT Libraries Government Documents Department