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Uniformly Reactive Uranium Dioxide from a Single Oxidation-Reduction Cycle

Description: Abstract: By use of a modified thermobalance and reactor as the primary experimental tool for sample preparation and evaluation, a process has been developed by which parent uranium feed materials of a widely variable reactivity and composition may be converted to a uniformly reactive uranium dioxide.
Date: August 28, 1963
Creator: Orrick, N. C.; Jones, C. G.; Hale, C. F.; Barber, E. J. & Rapp, Karl E.
Partner: UNT Libraries Government Documents Department

The Reactivity of Uranium and Blacosolv

Description: Abstract: "Blacosolv, trichloroethylene, is used in degreasing uranium metal. Tests were made under possible industrial conditions to determine whether a hazardous reaction between uranium and Blacosolv could occur. Temperature-rise measurements showed that there was no reaction of the metal, in various states of subdivision, with Blacosolv at temperatures up to 850 F. However, a reaction was observed in tests under which the finely divided metal, wet with solvent, was subjected to a severe impact."
Date: January 21, 1955
Creator: Hannan, H. D.; Miller, P. D. & Peoples, R. S.
Partner: UNT Libraries Government Documents Department

Reactivity Studies During Drying and Relocation of Lead-Zinc-Gold Tailings: Phase 1 - Preliminary Evaluation and Laboratory Testing

Description: The U.S. Bureau of Reclamation requested U.S. Bureau of Mines (USBM) assistance in developing design data for moving lead-zinc-gold tailings from their current location without disrupting the existing chemically stable conditions. This report presents results of USBM work in determining (1) the minimum required time to air dry the tailings to approximately 20 pct moisture under various drying conditions both in the laboratory and in the field, (2) the degree of oxidation or reduction that occurs during drying, (3) the effect of lime or cement addition before drying, and (4) the likely equilibrium conditions of the dried tailings after deposition at the new location. The limited number of tests performed by the USBM in the available time frame established trends in oxidation levels but did not provide absolute statistical validity of data values. All data from drying and oxidation testing are included in appendices to this report.
Date: 1995
Creator: Froisland, L. J. & Lym, P. B.
Partner: UNT Libraries Government Documents Department

SNAPTRAN 2/10A-3 destructive test results

Description: Report regarding a rapid water immersion test on a SNAP 10A/2 reactor core. It includes the radiological results of the tests and the reactor behavior that influenced these results.
Date: 1965
Creator: Brockett, George F.; Fletcher, R. D. (Robert Dearborn), 1917-; Dinneen, G. A.; Cordes, O. L. & Kessler, W. E.
Partner: UNT Libraries Government Documents Department

The Effect of Relationship Quality on Mental Representations of Social Support and Cardiovascular Reactivity

Description: The aim of the current study was to examine how thinking about qualitatively different social network members may differentially affect cardiovascular reactivity to a subsequent stressor. Eighty-two undergraduates were asked to think and write about different types of relationships preceding a social stressor. No differences between conditions in CVR were found during social support induction phase or the stressor task. Women in the supportive condition were found to have slower SV recovery than those in the ambivalent condition. The results of this study are inconsistent with previous evidence for a relationship between mental representations of social ties and CVR. Future research should seek to rule out confounding variables and clarify this effect.
Date: May 2011
Creator: Prather, Courtney C.
Partner: UNT Libraries

Investigation of Reactivity Anomalies in EBR-II

Description: A data-collection and advisory team was formed to investigate observations of power reactivity decrement (PRD) and reactivity loss rate (RLR) obtained during EBR-II reactor run 74, because both the PRD and RLR were judged to be high during that run. This report describes the efforts to develop a realistic model explaining the reactivity observations for run 74 and presents recommendations for additional diagnostic information in the event of a recurrence of off-normal behavior of reactivity.
Date: June 1976
Creator: Walters, L. C.; Cutforth, D. S.; Forehand, H. M.; Hudman, G. D.; Larson, H. A.; MacFarlane, H. F. et al.
Partner: UNT Libraries Government Documents Department

Reactor Kinetics: A Bibliography

Description: ABS>A bibliography covering the material listed in Nuclear Science Abstracts and Abstracts of Classified Reports up to July 1958 is presented. It is divided into 39 sections with author and report number indexes and a glossary of abbreviations. Each subject group has the entries by author onder, or by title (if no author listed). Each entry has a number so as to assist the location of reports from either the author or number indexes. While this biblicgraphy includes classified reports (indicated by AEC Classified), there are no classified titles. Publication dates of reports are given, when available, except where a date shows in the title, such as in progress reports. The report number index may be of special value to those researchers who desire all of one company's reports on this subject. (auth)
Date: November 1, 1959
Creator: Bloomfield, M. & Bennet, F.G.
Partner: UNT Libraries Government Documents Department

Notes on Evaporation of Target Materials

Description: Abstract: "The general utility of vacuum evaporated films is discussed. The characteristics that makes this technique most useful are the uniformity of the films, the easy control of their thickness over a large range, and the adaptability of the system to different metals and compounds. The design of a vacuum evaporator should provide adequate pumping speed, cooling of components, filament heater supply, and general flexibility and adaptability of the components to different materials. The design of filaments or boats and the evaporation of Al, Ag, Au, Li, Na, UCl4, ThF4, Be, SiO, Nal (Tl), U, and UO2 are considered. Special attention is given to the problem of obtaining uniform layers of UO2 on a large, flat target relatively close to the source."
Date: March 1953
Creator: Northrop, J. A. & Stokes, R. H.
Partner: UNT Libraries Government Documents Department

A Transistorized Reactivity Measurement System

Description: An all-transistor system has been developed to be used in measuring the reactivity of the reactor in the Sandia Engineering Reactor Facility. In operation, the system triggers a pulsed neutron source (PNS) in the reactor and counts the resulting neutron flux, thus giving a measure of the time constant of the reactor. The counting is done in eleven time-sequenced counting channels. The reactor time constant is a measure of the reactor reactivity.
Date: July 6, 1960
Creator: Ehrman, Leonard
Partner: UNT Libraries Government Documents Department

Terminal Status Report for the Processing Refabrication Experiment

Description: Introduction: A low-capacity, low-decontamination plant can be built, as part of a power reactor complex, to avoid long distance transfer of fuel to a high-capacity aqueous processing plant. Activation of such a complex, with the processing plant adjacent to the reactor it serves, could decrease the cost of the integrated fuel cycle. The study of this concept is a major objective of the Processing Refabrication Experiment (PRE).
Date: November 15, 1959
Creator: Sinizer, D. I.; Mattern, K. L. & Kendall, E. G.
Partner: UNT Libraries Government Documents Department

Nice Dissertation, for a Girl: Cardiovascular and Emotional Reactivity to Gender Microaggressions

Description: Gender microaggressions are normative messages that communicate harmful stereotypes or attitudes towards women. Research suggests that being the target of microaggresions may contribute to negative mental and physical health outcomes. The current study examined how gender microaggressions affect emotional and physiological reactivity as well as performance on a working memory task. Results indicated condition (i.e., control vs. sexual objectification microaggression vs. denial of sexism microaggression) did not have a significant affect on reactivity or performance. Issues of population bias and essentialism may have played an important role in study findings. Future directions are discussed.
Date: August 2015
Creator: Prather, Courtney C.
Partner: UNT Libraries

ENGINEERING APPLICATIONS OF ANALOG COMPUTERS

Description: Six examples are given of the application of analog computers in the fields of reactor engineering, heat transfer, and dynamics: deceleration of a reactor control rod by dashpot, pressure variations through a packed bed, reactor kinetics over many decades with thermal feedback (simulation of a TREAT transient), vibrating system with two degrees of freedom, temperature distribution in a radiating fin, and temperature distribution in an irfinite slab with variable thermal properties. (D.L.C.)
Date: February 1, 1961
Creator: Bryant, L.T.; Janicke, M.J.; Just, L.C. & Winiecki, A.L.
Partner: UNT Libraries Government Documents Department

MCNP/MCNPX model of the annular core research reactor.

Description: Many experimenters at the Annular Core Research Reactor (ACRR) have a need to predict the neutron/gamma environment prior to testing. In some cases, the neutron/gamma environment is needed to understand the test results after the completion of an experiment. In an effort to satisfy the needs of experimenters, a model of the ACRR was developed for use with the Monte Carlo N-Particle transport codes MCNP [Br03] and MCNPX [Wa02]. The model contains adjustable safety, transient, and control rods, several of the available spectrum-modifying cavity inserts, and placeholders for experiment packages. The ACRR model was constructed such that experiment package models can be easily placed in the reactor after being developed as stand-alone units. An addition to the 'standard' model allows the FREC-II cavity to be included in the calculations. This report presents the MCNP/MCNPX model of the ACRR. Comparisons are made between the model and the reactor for various configurations. Reactivity worth curves for the various reactor configurations are presented. Examples of reactivity worth calculations for a few experiment packages are presented along with the measured reactivity worth from the reactor test of the experiment packages. Finally, calculated neutron/gamma spectra are presented.
Date: October 1, 2006
Creator: DePriest, Kendall Russell; Cooper, Philip J. & Parma, Edward J., Jr.
Partner: UNT Libraries Government Documents Department

REACTIVITY OF SUBSTITUTION ELEMENTS

Description: A method is sought for predicting reactivity differences between fuel elements attached to control absorbers and fixed fuel elements. The approach described is based on a logic that is approximate, and which should be subjected to experimental check. (auth)
Date: January 19, 1959
Creator: Murray, R.L.
Partner: UNT Libraries Government Documents Department