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Millisecond Kinetics of Nanocrystal Cation Exchange Using Microfluidic X-ray Absorption Spectroscopy

Description: We describe the use of a flow-focusing microfluidic reactorto measure the kinetics of theCdSe-to-Ag2Se nanocrystal cation exchangereaction using micro-X-ray absorption spectroscopy (mu XAS). The smallmicroreactor dimensions facilitate the millisecond mixing of CdSenanocrystal and Ag+ reactant solutions, and the transposition of thereaction time onto spatial coordinates enables the in situ observation ofthe millisecond reaction with mu XAS. XAS spectra show the progression ofCdSe nanocrystals to… more
Date: May 7, 2007
Creator: Chan, Emory M.; Marcus, Matthew A.; Fakra, Sirine; Elnaggar, Mariam S.; Mathies, Richard A. & Alivisatos, A. Paul
Partner: UNT Libraries Government Documents Department
open access

Synthesis and Manipulation of Semiconductor Nanocrystals in Microfluidic Reactors

Description: Microfluidic reactors are investigated as a mechanism tocontrol the growth of semiconductor nanocrystals and characterize thestructural evolution of colloidal quantum dots. Due to their shortdiffusion lengths, low thermal masses, and predictable fluid dynamics,microfluidic devices can be used to quickly and reproducibly alterreaction conditions such as concentration, temperature, and reactiontime, while allowing for rapid reagent mixing and productcharacterization. These features are particular… more
Date: December 19, 2006
Creator: Chan, Emory Ming-Yue
Partner: UNT Libraries Government Documents Department
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Worker productivity and ventilation rate in a call center: Analyses of time-series data for a group of registered nurses

Description: We investigated the relationship of ventilation rates with the performance of advice nurses working in a call center. Ventilation rates were manipulated; temperatures, humidities, and CO{sub 2} concentrations were monitored; and worker performance data, with 30-minute resolution, were collected. Multivariate linear regression was used to investigate the association of worker performance with indoor minus outdoor CO{sub 2} concentration (which increases with decreasing ventilation rate per worke… more
Date: August 2003
Creator: Fisk, William J.; Price, Phillip; Faulkner, David; Sullivan, Douglas & Dibartolomeo, Dennis
Partner: UNT Libraries Government Documents Department
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Physics goals of a {mu}{sup +} {mu}{sup {minus}} collider

Description: This working group report focuses on the physics potential of {mu}{sup +}{mu}{sup {minus}} colliders beyond what can be accomplished at linear e{sup +}e{sup {minus}} colliders and the LHC. Particularly interesting possibilities include (1) s-channel resonance production to discover and study heavy Higgs bosons with ZZ and WW couplings that are suppressed or absent at tree-level (such as the H and A Higgs bosons of supersymmetric models), (2) study of the strongly interacting electroweak sector,… more
Date: March 1995
Creator: Barger, V.; Berger, M. S. & Fujii, K.
Partner: UNT Libraries Government Documents Department
open access

Negative Binomial Rits to Multiplicity Distributions From Central Collisions of {sup 16}O + Cu at 14.6A GeV/c and Intermittency

Description: An `intermittency` analysis of charged particle multiplicity data from the target multiplicy array (TMA) in central collisions of {sup 16}O+Cu at 14.6 A{times}GeV/c has been published by the AGS-E802 collaboration. The centrality cut was made using the Zero degree Calorimeter and requiring that the forward energy be less than one projectile nucleon (i.e. T{sub ZCAL} <13.6 GeV). In agreement with previous measurements, an apparent power-law growth of Normalized Factorial moments with decreasing … more
Date: October 14, 1994
Creator: Tannenbaum, M. J.
Partner: UNT Libraries Government Documents Department
open access

CIEE 1993 annual conference: Program

Description: The California Institute for Energy efficiency`s third annual conference highlights the results of CIEE-sponsored multiyear research in three programs: Building Energy Efficiency, Air Quality Impacts of Energy Efficiency, and End-Use Resource Planning. Results from scoping studies, Director`s discretionary research, and exploratory research are also featured.
Date: August 1, 1993
Partner: UNT Libraries Government Documents Department
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Recent results from E802 and E859

Description: Recent single-particle inclusive measurements and two-particle correlation data from E802 and its successor, E859, are presented. The K{sup +}/{pi}{sup +} ratio observed for collisions of 14.6 A{center dot} {sup 28}Si ions on various targets is presented as a function of both forward and transverse energy. Source sizes are determined via interferometry using {pi}{sup +}, {pi}{sup {minus}}, K{sup +} and proton pairs.
Date: January 1, 1991
Creator: Zajc, W. A.
Partner: UNT Libraries Government Documents Department
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Target rapidity proton distributions for Si+A collisions at the AGS

Description: Preliminary results are presented for the production of protons in 14.6 A{center dot}GeV/c Si+Al and Si+Au collisions measured by the E859 Phoswich Array at the BNL AGS. The proton data presented cover the laboratory angles of 50--130 degrees and kinetic energies of 40--180 MeV. Slopes and integrated distributions are extracted and comparisons with other experimental data are discussed.
Date: 1991
Creator: Costales, J. B.
Partner: UNT Libraries Government Documents Department
open access

Access to Film and Video Works: Surrogates for Moving Image Documents

Description: This doctoral dissertation discusses access to film and video works. Physical and intellectual access to moving image documents is insufficient, often insignificant, at the level of the individual user. Existing access tools suffer from a lack of recognition of the differences between linguistic text communication and image communication. Browsing and relevance judgements are made difficult by the physical realities of film and video documents - one cannot flip through them - and by the habits … more
Date: 1984
Creator: O'Connor, Brian Clark
Partner: UNT College of Information
open access

Research in the Geysers-Clear Lake Geothermal Area, Northern California

Description: From abstract: The Geysers-Clear Lake geothermal area lies within the central belt of the Franciscan assemblage in northern California. The structure of this terrane is characterized by northeast-dipping imbricate thrust slices that have been warped and cut by steeply dipping strike-slip and normal faults. Introduction of magma into the crust beneath the Geysers-Clear Lake area can be related to eastsoutheast extension accompanying northward propagation of the San Andreas transform system betwe… more
Date: 1981
Creator: McLaughlin, Robert J. & Donnelly-Nolan, Julie M.
Partner: UNT Libraries Government Documents Department
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The Influence of Point Defects on the Mechanical Properties of Lithium Fluoride : First Technical Report

Description: Lithium fluoride crystals were quenched into silicone oil from near the melting point. The return to an equilibrium structure during annealing was observed by means of mechanical tests and etching techniques. Crystals containing three levels of impurity, zone refined, commercially pure, and doped with 0.05 mole per cent magnesium, were used in order to separate the effects of foreign ions from those of thermal vacancies. The changes of mechanical properties produced by quenching and by subseque… more
Date: January 1960
Creator: Nadeau, J. & Washburn, J.
Partner: UNT Libraries Government Documents Department
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Nuclear Interactions in Carbon Produced by Cosmic Ray with Energies Between 10(10) and 10(12) ev.

Description: An experiment is described in which high energy nuclear interactions in the range of energies 10(10)-10(12)ev were analyzed by means of a cloud chamber n a magnetic field. Measurements of ionization and momentum made possible the identification of electrons and mesons to about 20 Bev/c. Protons, K-mesons and hyperons could not be identified unambiguously among themselves, except in very limited regions of momentum. The primary particles were cosmic-ray nucleons and a possible fraction of Pions,… more
Date: December 1959
Creator: Hansen, Luisa Fernandez
Partner: UNT Libraries Government Documents Department
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Underground Movement of Radioactive Wastes

Description: The theory and preliminary laboratory investigations presented in this technical report were intended to examine the general feasibility of injection disposal of radioactive wastes and to establish an understanding of the phenomena governing the travel of trace chemicals through natural porous media. Detailed studies of fluid velocity variations resulting from density differences between the injected and displaced liquids have been made. the ion exchange studies have been limited to strontium a… more
Date: August 1, 1955
Creator: Kaufman, Warren J., 1922-; Orcutt, Richard G., 1924- & Klein, Gerhard, 1918-1987
Partner: UNT Libraries Government Documents Department
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Fundamentals of Glass-to-Metal Bonding. [Part] 5-A. Temperature and Pressure Dependence of the Wettability of Metals by Glass. [Part] 5-B. Reactions of Tantalum and sodium Silicate Glass. Technical Report No. 5

Description: Part A. The major effort during the past year has been the construction of a suitable vacuum furnace for studying the effects of temperature and pressure on the wettability of metals by glass. A systems was completed that was capable of subjecting test combinations up to temperatures of 1400 degree C at a working pressure of 1 x 10(-5) mm. of Hg. Part B. A compound, identified by X-ray analysis as sodium meta tantalate (na2Ta2O6), was found at the interface between a sodium silicate glass and t… more
Date: June 24, 1955
Creator: Fulrath, Richard M.; Mitoff, Stephan P. & Pask, Joseph A. (Joseph Adam), 1913-2003.
Partner: UNT Libraries Government Documents Department
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The Charge on Uranium(VI) in Acid Solution

Description: Abstract. The distribution coefficient of U(VI) between perchloric acid solutions and benzene solutions of TTA has been measured as a function of the acidity. It was possible to interpret the data in terms of the charge on the U(VI) species present in the aqueous phase. The experiments indicate that U(VI) exists as an ion charge +2 at acidities from 0.1M to 2.5M. In the interpretations of the distribution data, it was necessary to know the acidity coefficient of the uranyl chelate in the ben… more
Date: August 15, 1946
Creator: King, Edward L.
Partner: UNT Libraries Government Documents Department
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An investigation of aircraft heaters 24: the heat meter in the transient state for unidirectional heat transfer

Description: Report describing the behavior of the heat meter when it is used in thermal circuits which are under the influence of transient potentials. Three scenarios are considered: a heat meter suddenly placed on a hot surface, a heat meter mounted on the interior surface of the cabin wall of an uninsulated airplane climbing through air of decreasing temperature, and a heat meter mounted on the interior surface of the composite cabin wall of an airplane climbing through air of decreasing temperature.
Date: September 1944
Creator: Boelter, L. M. K.; Poppendiek, H. F.; Dunkle, R. V. & Gier, J. T.
Partner: UNT Libraries Government Documents Department
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An Investigation of Aircraft Heaters 14: Performance of Two Finned-Type Crossflow Exhaust Gas and Air Heat Exchangers

Description: Report presenting data on the thermal performance and the static pressure drop characteristics of two finned-type exhaust gas and air heat exchangers. One heater was constructed of copper and stainless steel while the other was constructed from aluminum alloy. The measured thermal outputs and static pressure drops are compared with predicted magnitudes.
Date: August 1944
Creator: Boelter, L. M. K.; Guibert, A. G.; Rademacher, J. M. & Sloggy, L. J. B.
Partner: UNT Libraries Government Documents Department
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An investigation of aircraft heaters 17: experimental inquiry into steady state unidirectional heat-meter corrections

Description: Report divided into two sections. One discusses a correction that must be applied to a heat meter when it is used at temperatures other than temperatures at which it was calibrated. The other section contains the results of an application of the two methods of correcting the heat-transfer rates for contact and heat-meter resistance to experimental data.
Date: August 1944
Creator: Boelter, L. M. K.; Poppendiek, H. F. & Gier, J. T.
Partner: UNT Libraries Government Documents Department
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An investigation of aircraft heaters 16: determination of the viscosity of exhaust gases from a gasoline engine

Description: Report presenting an investigation which found that the absolute viscosity of exhaust gases from a gasoline engine was measured at a range of temperatures and compositions. Results regarding preliminary runs, calibration runs at room temperature, check runs at medium temperatures, and exhaust gas measurements are provided.
Date: June 1944
Creator: Boelter, L. M. K. & Sharp, W. H.
Partner: UNT Libraries Government Documents Department
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An investigation of aircraft heaters 14: an air and heat flow analysis of a ram-operated heater and duct system

Description: Report presenting a method of graphical analysis that allows for the prediction of the thermal and aerodynamic performance of a ram-operated heater and duct system, for cabin heating or wing de-icing, at any altitude and airplane speed. Performance can be predicted from the isothermal total pressure drop across the components of the duct system at several ventilating air rates and the thermal output of the heater at various air and exhaust gas rates.
Date: March 1944
Creator: Boelter, L. M. K.; Morrin, E. H.; Martinelli, R. C. & Poppendiek, H. F.
Partner: UNT Libraries Government Documents Department
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An investigation of aircraft heaters 15: the emissivity of several materials

Description: Report presenting a determination of the mean effective emissivity as a function of temperature for the surfaces of several metals and insulating materials. A description and discussion of the measuring technique is presented. The results are plotted on a variety of graphs.
Date: January 1944
Creator: Boelter, L. M. K.; Bromberg, R. & Gier, J. T.
Partner: UNT Libraries Government Documents Department
open access

An investigation of aircraft heaters 13: performance of corrugated and noncorrugated fluted type exhaust gas-air heat exchangers

Description: Report presenting thermal and static pressure-drop performance data on three fluted-type heat exchangers. Two of the heaters used corrugated surfaces along the fluid passages and the third one was constructed with non-corrugated surfaces. Results regarding a comparison of results on the noncorrugated heater using two different air shrouds, heat transfer, isothermal static pressure drop, nonisothermal static pressure drop, and heater surface temperatures are provided.
Date: August 1943
Creator: Boelter, L. M. K.; Guibert, A. G.; Miller, M. A. & Morrin, E. H.
Partner: UNT Libraries Government Documents Department
open access

An investigation of aircraft heaters 12: performance of a formed-plate crossflow exhaust gas and air heat exchanger

Description: Report presenting performance data on a Trane exhaust gas and air heat exchanger. Heat transfer rates were measured using specified exhaust gas rates and ventilating-air rates. The measured thermal outputs and static pressure drops are compared with predicted magnitudes.
Date: May 1943
Creator: Boelter, L. M. K.; Dennison, H. G.; Guibert, A. G. & Morrin, E. H.
Partner: UNT Libraries Government Documents Department
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