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Development of an Aging Integrator for Uranium-0.75 Weight Percent Titanium Alloy Part Aging Control

Description: An instrumentation system (Aging Integrator) has been developed to provide more precise control of the heat-treatment process used on uranium-0.75 weight percent titanium alloy material. The Aging Integrator calculates the integral of a predetermined aging function to control the aging period in the heat-treatment process. This control was employed to compensate for discrepancies caused by variations in heatup times, furnace-control fluctuations, and disagreement as to the temperature at which … more
Date: December 1, 1977
Creator: Howington, L. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Nuclear power plant cable materials : review of qualification and currently available aging data for margin assessments in cable performance.

Description: A selective literature review was conducted to assess whether currently available accelerated aging and original qualification data could be used to establish operational margins for the continued use of cable insulation and jacketing materials in nuclear power plant environments. The materials are subject to chemical and physical degradation under extended radiationthermal- oxidative conditions. Of particular interest were the circumstances under which existing aging data could be used to pred… more
Date: May 1, 2013
Creator: Celina, Mathias Christopher; Gillen, Kenneth Todd & Lindgren, Eric Richard
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Peripheral Circulating Exosomal miRNAs Potentially Contribute to the Regulation of Molecular Signaling Networks in Aging

Description: This article aims to understand some of the causes of aging and the underlying mechanisms that may lead to interventions that could reverse certain aging processes and slow development of aging-related diseases. People are living longer than ever. Consequently, they have a greater chance for developing a functional impairment or aging-related disease, such as a neurodegenerative disease, later in life.
Date: March 11, 2020
Creator: Zhang, Hongxia & Jin, Kunlin
Item Type: Refine your search to only Article
Partner: UNT Health Science Center
open access

Spinodal Decomposition and Order-Disorder Transformation in a Water-Quenched U-6wt%Nb Alloy

Description: A combinative approach of microhardness testing, tensile testing, and TEM microstructural analysis has been employed to study phase stability and aging mechanisms of a water-quenched U-6wt%Nb (WQU6Nb) alloy subjected to different aging schedules that include artificial aging of WQ-U6Nb at 200 C, natural aging of WQ-U6Nb at ambient temperatures for 15 to18 years, and accelerative aging of the naturally aged (NA) alloy at 200 C. During the early stages of artificial aging at 200 C, the microhardn… more
Date: September 12, 2006
Creator: Hsiung, L & Zhou, J
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Dose Rate Evaluation for Spent Fuel Aging Areas at Yucca Mountain

Description: The spent nuclear fuel (SNF) aging system at the proposed Yucca Mountain repository will provide site-specific casks and aging pads for thermal management of commercial SNF with a heat rate in excess of the waste package thermal output limit. An aging pad can accommodate 1,000 MTHM of SNF, containing a total of 100 aging casks with a horizontal module of 20 casks, and 80 vertical site-specific casks arranged in a 2 x 40 array. The proposed aging system will provide five aging areas in two separ… more
Date: January 7, 2005
Creator: Radulescu, G. & Su, Shiaw-Der
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Microstructure and Mechanical Instability of Water-Quenched U-6wt% Nb Alloy Affected by Long-Term Aging

Description: A combinative approach of microhardness testing, tensile testing, and TEM microstructural analysis was employed to study the microstructure and mechanical instability of a water-quenched U-6wt.% Nb (WQ-U6Nb) alloy subjected to different aging schedules including artificial aging at 200 C, 15-year natural aging at ambient temperatures, and 15-year natural aging followed by accelerative aging at 200 C. The changes in mechanical property during and after the aging processes were examined using mic… more
Date: December 6, 2005
Creator: Hsiung, L & Zhou, J
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

[Clipping: Artists interpret aging]

Description: Newspaper clipping from the Denton Record-Chronicle. The article, Artists interpret aging, was written in regards to the "Images in Aging" exhibition at the North Texas State University Historical Collection in which artists will display their interpretations of aging.
Date: unknown
Item Type: Refine your search to only Clipping
Partner: UNT Libraries Special Collections
open access

The effect of chrome adhesion layer on quartz resonator aging.

Description: This SAND report documents a late start LDRD designed to determine the possible aging effects of a quartz resonator gold adhesion layer. Sandia uses quartz resonators for applications. These applications require a very stable frequency source with excellent aging (low drift) characteristics. These parts are manufactured by one of our qualified vendors outside Sandia Laboratories, Statek Corp. Over the years we, Sandia and the vendor, have seen aging variations that have not been completely expl… more
Date: March 1, 2011
Creator: Wessendorf, Kurt O. & Ohlhausen, James Anthony
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Plant maintenance and aging management: Are they the same?

Description: As part of the NRC`s Nuclear Plant Aging Research Program, a number of aging studies were performed on safety-related systems and components which found that, even with current maintenance and monitoring practices in place, a large number of the reported failures are related to aging. This suggests that current practices are not sufficient to completely manage aging degradation, and other factors need to be considered. This paper examines the aging management process and the degree to which mai… more
Date: June 1, 1995
Creator: Lofaro, R.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Aging Texas Well: An Assessment of Denton's Aging-Friendliness

Description: The purpose of this research was to conduct a needs assessment for the city of Denton, Texas to learn how residents view Denton's aging-friendliness. The research design was based on the Texas Department of Aging and Disability Services' Aging Texas Well Toolkit and was funded by a two year grant from that agency. Both qualitative and quantitative methods were used to gather data on six community indicators: demographics, housing, transportation, health care (including mental health and substan… more
Date: August 2016
Creator: Wolfe, Julia Rachel Weinstein
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Long-Term Phase Instability in Water-Quenched U-6Nb

Description: A combinative approach of microhardness testing, tensile testing, and TEM microstructural analysis was employed to study the microstructure and mechanical instability of a water-quenched U-6wt.% Nb (WQ-U6Nb) alloy subjected to different aging schedules including artificial aging at 200 C, 15-year natural aging at ambient temperatures, and 15-year natural aging followed by accelerative aging at 200 C. The changes in mechanical property during and after the aging processes were examined using mic… more
Date: January 16, 2006
Creator: Hsiung, L L & Zhou, J
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Spinodal Ordering and Precipitation in U-6 wt% Nb

Description: A combinative approach of microhardness testing, tensile testing, and TEM microstructural analysis was employed to study the microstructure and mechanical instability of a water-quenched U-6wt.% Nb (WQU6Nb) alloy subjected to different aging schedules including artificial aging at 200 C, 15-year natural aging at ambient temperatures, and 15-year natural aging followed by accelerative aging at 200 C. The changes in mechanical property during and after the aging processes were examined using micr… more
Date: December 19, 2005
Creator: Hsiung, L & Zhou, J
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Program Plan for Acquiring and Examining Naturally Aged Materials and Components from Nuclear Reactors

Description: This project was funded through the Nuclear Plant Optimization Program (NEPO)to develop an integrated plan to indentify aging issues that can be effectively addressed by investigating the condition of naturally aged components, materials,and structures (CMSs)from nuclear power plants (NPPs. As operating periods for the NPPs increase, there is a need to access selected CMSs for continuing assurance that aging issues are understood and effectively managed; also, that benchmarking of existing mode… more
Date: July 10, 2002
Creator: Johnson, A. Burton; Sundaram, S. K. & Garner, Francis A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Design Evolution Study - Aging Options

Description: The purpose of this study is to identify options and issues for aging commercial spent nuclear fuel received for disposal at the Yucca Mountain Mined Geologic Repository. Some early shipments of commercial spent nuclear fuel to the repository may be received with high-heat-output (younger) fuel assemblies that will need to be managed to meet thermal goals for emplacement. The capability to age as much as 40,000 metric tons of heavy metal of commercial spent nuclear he1 would provide more flexib… more
Date: April 5, 2002
Creator: McDaniel, P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Validation issues in aging risk evaluations

Description: Validation issues in aging risk evaluations are examined by considering how variabilities and uncertainties due to sparse component aging data, modeling assumptions, and risk quantification approaches may affect aging risk evaluation results and inferences. Sensitivity studies using a NUREG-1150 PWR evaluated the effect of component aging data uncertainties and variations in test and maintenance frequencies on aging prioritizations. Preliminary results indicate that while individual component r… more
Date: July 1, 1992
Creator: Hassan, M.; Samanta, P. & Vesely, W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

AGING FACILITY WORKER DOSE ASSESSMENT

Description: The purpose of this calculation is to estimate radiation doses received by personnel working in the Aging Facility performing operations to transfer aging casks to the aging pads for thermal and logistical management, stage empty aging casks, and retrieve aging casks from the aging pads for further processing in other site facilities. Doses received by workers due to aging cask surveillance and maintenance operations are also included. The specific scope of work contained in this calculation co… more
Date: March 24, 2005
Creator: Thacker, R.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Validation issues in aging risk evaluations

Description: Validation issues in aging risk evaluations are examined by considering how variabilities and uncertainties due to sparse component aging data, modeling assumptions, and risk quantification approaches may affect aging risk evaluation results and inferences. Sensitivity studies using a NUREG-1150 PWR evaluated the effect of component aging data uncertainties and variations in test and maintenance frequencies on aging prioritizations. Preliminary results indicate that while individual component r… more
Date: January 1, 1992
Creator: Hassan, M.; Samanta, P. (Brookhaven National Lab., Upton, NY (United States)) & Vesely, W. (Science Applications International Corp., San Diego, CA (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Effective maintenance practices to manage system aging

Description: For a variety of economic and technical reasons, there has been a growing concern with the aging of complex systems and components and the role that maintenance can play in reducing this degradation. A study for the Nuclear Regulatory Commission was recently undertaken to identify effective maintenance practices that could be adapted by the nuclear industry in the United States to assist in managing the aging degradation of plant systems and components. Four organizations were examined to asses… more
Date: January 1, 1992
Creator: Chockie, A. & Bjorkelo, K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Effective maintenance practices to manage system aging

Description: For a variety of economic and technical reasons, there has been a growing concern with the aging of complex systems and components and the role that maintenance can play in reducing this degradation. A study for the Nuclear Regulatory Commission was recently undertaken to identify effective maintenance practices that could be adapted by the nuclear industry in the United States to assist in managing the aging degradation of plant systems and components. Four organizations were examined to asses… more
Date: January 1, 1992
Creator: Chockie, A. & Bjorkelo, K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

EIGHTH INTERIM STATUS REPORT: MODEL 9975 PCV O-RING FIXTURE LONG-TERM LEAK PERFORMANCE

Description: A series of experiments to monitor the aging performance of Viton® GLT O-rings used in the Model 9975 package has been ongoing since 2004 at the Savannah River National Laboratory. Seventy tests using mock-ups of 9975 Primary Containment Vessels (PCVs) were assembled and heated to temperatures ranging from 200 to 450 ºF. They were leak-tested initially and have been tested periodically to determine if they meet the criterion of leak-tightness defined in ANSI standard N14.5-97. Fourteen addition… more
Date: September 3, 2013
Creator: Daugherty, W. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Aging in large CDF tracking chambers

Description: The experience of the Collider Detector at Fermilab (CDF) with aging in the large axial drift chamber responsible for tracking in the central region is presented. Premature aging in the Run 1 chamber was observed after only 0.02 C/cm. After cleaning much of the gas system and making modifications to reduce aerosols from the alcohol bubbler, the observed aging rate fell dramatically in test chambers. Considerable effort has been made to better understand the factors that affect aging since the r… more
Date: March 19, 2001
Creator: al., M. Binkley et
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

AGING FACILITY CRITICALITY SAFETY CALCULATIONS

Description: The purpose of this design calculation is to revise and update the previous criticality calculation for the Aging Facility (documented in BSC 2004a). This design calculation will also demonstrate and ensure that the storage and aging operations to be performed in the Aging Facility meet the criticality safety design criteria in the ''Project Design Criteria Document'' (Doraswamy 2004, Section 4.9.2.2), and the functional nuclear criticality safety requirement described in the ''SNF Aging System… more
Date: September 10, 2004
Creator: Sanders, C.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A Survey of Collaborative Efforts Between Public Health and Aging Services Networks in Community Health Centers in Texas

Description: Federally qualified health centers (FQHCs) that harness the reinforcing nature of collaborative efforts with aging services can better prepare for the future of older adult populations. The purpose of this research was to identify collaborative efforts between FQHCs and aging services and distinguish perceptions and knowledge regarding older adult populations. Executive directors, medical directors and social service directors (N=44) at 31 FQHCs across the state of Texas completed surveys measu… more
Date: May 2009
Creator: Severance, Jennifer Jurado
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Managing the effects of aging and reliability improvement

Description: Over recent years the electric power generating community has acknowledged the importance of the aging process on plant safety and availability. To cope with time-dependent degradation phenomenon that can affect active as well as passive components and lead to unacceptable, unanticipated failures requires research into the mechanisms of the aging process, advances in productive methods for assessing the aging impact on risk and availability, and a better understanding of power plant operations … more
Date: January 1, 1987
Creator: Hall, R.E.; Taylor, J.H. & Boccio, J.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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