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High-Sensitivity Single-Molecule Fluorescence Detection in Theory and Practice

Description: The number of emitted photons that can be obtained from a fluorophore increases with the incident light intensity and the duration of illumination. However, saturation of the absorption transition and photodestruction place natural limits on the ultimate signal-to-noise ratio that can be obtained. Equations have been derived to describe the fluorescence-to-background-noise ratio in the presence of saturating light intensities and photodestruction. The fluorescence lifetime and the photodestruction quantum yield are the key parameters that determine the optimum light intensity and exposure time. To test this theory we have performed single molecule detection of phycoerythrin (PE). The laser power was selected to give a mean time between absorptions approximately equal to the fluorescence decay rate. The transit time was selected to be nearly equal to the photodestruction time of {approximately}600 {mu}s. Under these conditions the photocount distribution function, the photocount autocorrelation function, and the concentration dependence clearly show that we are detecting bursts of fluorescence from individual fluorophores. A hard-wired version of this single-molecule detection system was used to measure the concentration of PE down to 10{sup {minus}15} M. This single-molecule counter is three orders-of-magnitude more sensitive than conventional fluorescence detection systems. The approach presented here should be useful in the optimization of fluorescence detected DNA sequencing gels. 17 refs., 4 figs.
Date: 1989
Creator: Mathies, R. A.; Peck, K. & Stryer, L.
Partner: UNT Libraries Government Documents Department
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Solar heating and domestic hot water system installed at Kansas City, Fire Station, Kansas City, Missouri. Final report

Description: This document is the final report of the solar energy heating and hot water system installed at the Kansas City Fire Station, Number 24, 2309 Hardesty Street, Kansas City, Missouri. The solar system was designed to provide 47 percent of the space heating, 8800 square feet area and 75 percent of the domestic hot water (DHW) load. The solar system consists of 2808 square feet of Solaron, model 2001, air, flat plate collector subsystem, a concrete box storage subsystem which contains 1428 cubic feet of 1/2 inch diameter pebbles weighing 71 1/2 tons, a DHW preheat tank, blowers, pumps, heat exchangers, air ducting, controls and associated plumbing. Two 120-gallon electric DHW heaters supply domestic hot water which is preheated by the solar system. Auxiliary space heating is provided by three electric heat pumps with electric resistance heaters and four 30-kilowatt electric unit heaters. There are six modes of system operation. This project is part of the Department of Energy PON-1 Solar Demonstration Program with DOE cost sharing $154,282 of the $174,372 solar system cost. The Final Design Review was held March 1977, the system became operational March 1979 and acceptance test was completed in September 1979.
Date: July 1980
Partner: UNT Libraries Government Documents Department
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Development of a computer program for reactor core thermal hydraulics: finite differencing in a 3-D staggered mesh suitable for irregular boundary applications

Description: A formulation utilizing a finite difference scheme for the direct numerical simulation of time varying two-phase flow problems in three space dimensions with irregular boundary geometry is presented. The formulation of such problems introduces a complicated set of coupled non-linear partial differential equations for the conservation of mass, momentum, energy, appropriate constitutive equations, and equations of state coupling the two phases. Discretization of the partial differential equations by finite difference procedures allows for numerical solution of the governing equations.
Date: unknown
Creator: Sha, W.T.
Partner: UNT Libraries Government Documents Department
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Scoping Report on Various Salt Mines in the United States

Description: One of the most important factors in isolating the demonstration waste storage site is an adequate number of shafts to insure proper ventilation. Proper ventilation will require that the air exhausted from the storage area pass directly to the upcast air shaft. Those mines reported by this scoping contract generally conform with the two shafts per mine requirement of MESA. Three of the mines reported on have more than two shafts. Several of the mines can have additional shafts drilled in time to meet ERDA's schedule. Rough drilling costs have been cited in the report. From an economic standpoint, it is probable that the larger the mine, the greater the economic impact with regard to any dislocation of production that may be required. In some cases, such as the Retsof Mine and the Cayuga Mine, multiple shafts eliminate the probability of dislocation. Those small tonnage mines such as the Kleer at Grand Saline, Texas; the Hockley Mine near Houston and the Lyons Mine of the American Salt Company might be leased or purchased in their entirety.
Date: July 1977
Creator: Jacoby, C. H.
Partner: UNT Libraries Government Documents Department
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Adaptive Mesh Refinement for 1-Dimensional Gas Dynamics

Description: We consider the solution of the one-dimensional equation of gas-dynamics. Accurate numerical solutions are difficult to obtain on a given spatial mesh because of the existence of physical regions where components of the exact solution are either discontinuous or have large gradient changes. Numerical methods treat these phenomena in a variety of ways. In this paper, the method of adaptive mesh refinement is used. A thorough description of this method for general hyperbolic systems is given elsewhere and only properties of the method pertinent to the system are elaborated.
Date: 1982-08~
Creator: Hedstrom, Gerald; Rodrigue, Garry; Berger, Marsha & Oliger, Joseph
Partner: UNT Libraries Government Documents Department
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Energy dependence of metallic-encapsulated thermoluminescent dosimeters. Annual report

Description: The gamma-ray energy responses of encapsulated /sup 7/LiF and CaF/sub 2/:Mn thermoluminescent dosimeters were measured and compred to calculated values. This study was performed in order to improve the accuracy of gamma-ray heating measurements made in polyenergetic gamma-ray fields such as Argonne National Laboratory's Zero Power Reactors. Equations used in the development of the TERC/III computer code and code input parameters are specified. A section on TLD precision is also included. Comparisons between calculations and experiments are reported for a gamma-ray energy range of 0.122 to 1.33 MeV and encasement media with a range of atomic numbers from 13 to 82.
Date: June 1980
Creator: Simons, G. G.
Partner: UNT Libraries Government Documents Department
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Results of the 1988 Geothermal Gradient Test Drilling Project for the State of Washington

Description: During late summer and early fall of 1988, the Washington Department of Natural Resources, Division of Geology and Earth Resources (DGER) completed drilling eight shallow geothermal gradient test wells in the southern Washington Cascade Range. This report describes the preliminary results of the 1988 drilling and gradient measuring, and summarizes our current perspectives on distribution and magnitude of the geothermal resource potential in the southern Washington Cascades. 18 refs., 11 figs., 11 tabs.
Date: May 1989
Creator: Barnett, D. B. & Korosec, M. A.
Partner: UNT Libraries Government Documents Department
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Theory of chemical kinetics. Progress report, May 1, 1977--January 15, 1978. [Massachusetts Inst. of Tech. , Cambridge]

Description: Recent work on Franck--Condon factors in studies of the dynamics of chemical reactions is related; emphasis was on simple chemical rearrangement reactions. Other work concerned collision-free unimolecular decomposition of large molecules at a given total energy, equations of motion for simple quantum systems that are strongly driven by an external field and are modulated stochastically by a coupling to a bath, and the efficiency of rate processes in irreversible chemical reactions. This report is descriptive in nature; results of the work have been published in appropriate journals, and an extensive publication list is included. (RWR)
Date: unknown
Creator: Ross, J.
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 exchange with sediments, and the role of micro-zooplankton in nutrient cycling.
Date: 1977~
Creator: Taft, Jay L.
Partner: UNT Libraries Government Documents Department
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High beta studies on ISX-B with neutral beam injection

Description: Injection of H/sup 0/ into D/sup +/ plasmas with beam power P/sub b/ of up to 1.7 MW has produced rms betas of approx. 4%, volume-averaged betas of approx. 3%, and central betas of approx. 10% in the ISX-B tokamak. Although theoretical calculations indicate that the observed equilibria may be unstable to ballooning modes, no catastrophic loss of confinement has been observed, and beta continues to increase with injection power. In these beam-dominated high-beta discharges the electron and ion energy confinement times are still similar to those obtained with ohmic heating: ion energy confinement is neoclassical within a factor of approx. 2, and electron energy confinement follows the usual Alcator scaling. In high-power injection discharges the character of the magnetohydrodynamic (MHD) behavior changes, the particle confinement time decreases, and the inward impurity transport appears to be inhibited. These effects, however, may not be linked directly to beta.
Date: September 1980
Creator: Sheffield, J.; Bates, S.C. & Bush, C.E.
Partner: UNT Libraries Government Documents Department
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Industrial fuel gas demonstration plant program. License agreements for proprietary processes. (Deliverable No. 30)

Description: The proprietary processes included within the Industrial Fuel Gas Demonstration Plant are listed. Draft license agreements covering the use of these processes, with the exception of the Westfield Process (Conoco), have been included at the end of this document. Except for the Claus Process (Amoco) all draft license agreements will be executed directly between MLGW and the licensor. All the draft license agreements provided have been prepared by the licensors after preliminary discussions. Presently these agreements are being reviewed by MLGW for acceptability. As stated above, the Amoco Sulfur Recovery Process will be covered by an existing agreement between Standard Oil and FWEC. Suitable clauses have been provided under Tab V. These clauses will be incorporated into the MLGW/FWEC subcontract for the protection of MLGW, FWEC, and licensor. At this writing the Industrial Team has no secrecy agreement executed with Conoco Methanation Company (Westfield Methanation Process) nor has any draft license agreement been transmitted by Conoco.
Date: unknown
Partner: UNT Libraries Government Documents Department
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Enthalpy measurement of coal-derived liquids. Combined quarterly technical progress reports, April-June 1979 and July-September 1979. [Effect of association]

Description: Enthalpy measurements on a coal-derived naphtha and middle distillate, both produced by the SRC-II process, were made using flow calorimetry. The accuracy of the measurements, as reported by Omid, was within +- 1% of the measured enthalpy differences, ..delta..H. Experimental data for the naphtha were obtained over a pressure range of 100-300 psia and temperatures from 148/sup 0/ to 456/sup 0/F. The middle distillate enthalpy measurements were made in the pressure and temperature ranges of 130 to 1000 psia, and 157/sup 0/ to 675/sup 0/F, respectively. The methods of prediction of enthalpy developed for petroleum fractions were unsatisfactory when applied to the above data. A negative bias was observed in the predicted enthalpy values for several of the coal-liquids. Based on these results, it was theorized that the high experimental enthalpy values for coal-liquids were due to an energy of association attributed, primarily, to hydrogen-bonding effects. The petroleum-fraction enthalpy correlations were then tested on the experimental data for pure compounds, both associating and non-associating. The predicted values compared very well with the experimental results for non-associating model compounds. However, for associating model compounds the predicted enthalpy values were considerably lower than their experimental data. This served to confirm the basic premise that the high experimental enthalpy values, for model compounds and coal liquids, were a direct consequence of an energy of association attributed, primarily, to hydrogen-bonding effects.
Date: 1979~
Creator: Kidnay, A. J. & Yesavage, V. F.
Partner: UNT Libraries Government Documents Department
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Pumping behavior of sputter ion pumps

Description: The ultrahigh vacuum requirements of ISABELLE is obtained by distributed pumping stations. Each pumping station consists of 1000 l/s titanium sublimation pump for active gases (N/sub 2/, H/sub 2/, O/sub 2/, CO, etc.), and a 20 l/s sputter ion pump for inert gases (methane, noble gases like He, etc.). The combination of the alarming production rate of methane from titanium sublimation pumps (TSP) and the decreasing pumping speed of sputter ion pumps (SIP) in the ultrahigh vacuum region (UHV) leads us to investigate this problem. In this paper, we first describe the essential physics and chemistry of the SIP in a very clean condition, followed by a discussion of our measuring techniques. Finally measured methane, argon and helium pumping speeds are presented for three different ion pumps in the range of 10/sup -6/ to 10/sup -11/ Torr. The virtues of the best pump are also discussed.
Date: unknown
Creator: Chou, T S & McCafferty, D
Partner: UNT Libraries Government Documents Department
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Low strain diameter expansion of internally pressurized Zircaloy-4 tubing at high temperatures

Description: Tests of closed-end, internally pressurized, Zircaloy-4 tubing specimens were utilized to develop low strain creep characteristics as a function of time at temperatures in the range of 1475/sup 0/F to 2000/sup 0/F (802/sup 0/C to 1093/sup 0/C) and hoop stresses in the range of 250 to 2500 psi for use in loss-of-coolant accident (LOCA) analyses. The strain rate above the start of the alpha to beta phase transformation region, approximately 1490/sup 0/F (810/sup 0/C), was found to be sensitive to the test procedure (stress-temperature history). This is believed to result from variations in the metallurgical structure. A prediction model is presented which provides a conservative upper bound to the low strain test data provided in this report and reported in the literature.
Date: March 1978
Creator: White, L.S. & Busby, C.C.
Partner: UNT Libraries Government Documents Department
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Neutron diffraction study of magnetic order in the ternary superconductor ErMo/sub 6/Se/sub 8/

Description: Synthesis of new classes of ternary superconducting materials has led to compounds which also show a strong tendency toward magnetic order when one of the constituent elements is a rare earth. Powder neutron diffraction data on superconducting (T/sub s/ approximately 6 K) samples of ErMo/sub 6/Se/sub 8/ taken in the temperature range 0.05 to 2.0 K show that magnetic Bragg peaks develop at T/sub M/ = 1.1 K, in agreement with specific heat studies. However, it is not possible to index these new reflections using a simple antiferromagnetic unit cell based on the ErMo/sub 6/Se/sub 8/ lattice. It is also not possible to index the magnetic reflections based on a single modulation vector, or with a modulation vector along a high symmetry direction including higher order harmonics. Thus either the long range magnetic order corresponds to a more complicated magnetic structure in the ErMo/sub 6/Se/sub 8/ lattice, or at least some of the peaks develop in impurity phases. These results are compared with the recent neutron data on the reentrant superconductors HoMo/sub 6/S/sub 8/ and ErRh/sub 4/B/sub 4/, in which the development of ferromagnetic order is clearly shown to be responsible for quenching the superconductivity.
Date: 1977~
Creator: Lynn, J. W.; Moncton, D. E.; Shirane, G.; Thomlinson, W.; Eckert, J. & Shelton, R. N.
Partner: UNT Libraries Government Documents Department
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Energy-consumption modelling

Description: A highly sophisticated and accurate approach is described to compute on an hourly or daily basis the energy consumption for space heating by individual buildings, urban sectors, and whole cities. The need for models and specifically weather-sensitive models, composite models, and space-heating models are discussed. Development of the Colorado State University Model, based on heat-transfer equations and on a heuristic, adaptive, self-organizing computation learning approach, is described. Results of modeling energy consumption by the city of Minneapolis and Cheyenne are given. Some data on energy consumption in individual buildings are included.
Date: April 1980
Creator: Reiter, Elmar R.
Partner: UNT Libraries Government Documents Department
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Annual Report on Wildlife Activities, 1985 Fiscal Year, Action Item 40.1, Columbia River Basin Fish and Wildlife Program.

Description: The report presents a brief synopsis and discussion of wildlife activities undertaken by Bonneville Power Administration. The objectives of the program were wildlife protection, mitigation, and enhancement planning; and implementation of actions to protect, mitigate, and enhance wildlife affected by development and operation of hydroelectric facilities in the Columbia River Basin. (ACR)
Date: September 1985
Creator: United States. Bonneville Power Administration. Division of Fish and Wildlife.
Partner: UNT Libraries Government Documents Department
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