Resource Type

101 Matching Results

Results open in a new window/tab.

The Interface Strengthening of Multi-Walled Carbon Nanotubes/Polylactic Acid Composites via the In-Loop Hybrid Manufacturing Method (open access)

The Interface Strengthening of Multi-Walled Carbon Nanotubes/Polylactic Acid Composites via the In-Loop Hybrid Manufacturing Method

Article describes how in this study, a new in-loop hybrid manufacturing method is proposed for fabricating multi-walled carbon nanotube (MWCNTs)/polylactic acid (PLA) composites. Molecular dynamics simulations were conducted in conjunction with experiments to reveal the mechanism of the proposed method for improving the interfacial performance of MWCNTs/PLA.
Date: November 16, 2023
Creator: Li, Hongbin; Jiang, Zhuang; Li, Zhihua; Peng, Yubao; Zhang, Qiushuang & Xiao, Xinyi
System: The UNT Digital Library
The Impact of COVID-19 Shocks on Business and GDP of Global Economy (open access)

The Impact of COVID-19 Shocks on Business and GDP of Global Economy

Article examines the relationship between COVID-19 shocks and GDP loss of different countries worldwide based on the seven scenarios of the epidemiological DSGE/CGE model. Their results reveal that the most significant GDP loss is associated with Japan, Germany, and the US, respectively, which are industrialized countries with the most prominent automobile manufacturers.
Date: November 16, 2022
Creator: Ahangar, Reza Gharoie & Kim, Myungsup
System: The UNT Digital Library
Novel thin polymeric magnetic membranes study for applications in the future biomedical devices (open access)

Novel thin polymeric magnetic membranes study for applications in the future biomedical devices

Article describes how biomedical devices such as pumping/mixing fluids, cell-culturing, and drug delivery often use different actuation methods. In regard to magnetic actuation, membranes with a local distribution of magnetic particles are investigated and compared to membranes with randomly distributed magnetic particles, which in turn may enhance the actuation performance for certain applications.
Date: November 16, 2022
Creator: Manzo, Maurizio & Bakaraju, Megha
System: The UNT Digital Library
Role of Electronic Healthcare Record Adoption in Enhancing the Relationship between Quality Measures and Hospital Financial Performance (open access)

Role of Electronic Healthcare Record Adoption in Enhancing the Relationship between Quality Measures and Hospital Financial Performance

Article asserts that the most significant government-mandated technology is the implementation of Electronic Health Records (EHRs). The present research examines EHR through the lens of Resource Advantage Theory –– to empirically assess how partial and comprehensive implementation levels of EHR adoption influence quality management and financial performance of hospitals.
Date: November 16, 2022
Creator: Malhan, Amit; Pavur, Robert J.; Pelton, Lou E. & Manuj, Ila
System: The UNT Digital Library
Breaking Health Insurance Knowledge Barriers Through Games: Pilot Test of Health Care America (open access)

Breaking Health Insurance Knowledge Barriers Through Games: Pilot Test of Health Care America

This article discusses the design and testing of an interactive newsgame about health insurance.
Date: November 16, 2017
Creator: Champlin, Sara & James, Juli
System: The UNT Digital Library
Deciphering pathogenicity and antibiotic resistance islands in methicillin-resistant Staphylococcus aureus genomes (open access)

Deciphering pathogenicity and antibiotic resistance islands in methicillin-resistant Staphylococcus aureus genomes

This article explores the use of an information-entropy-based gene clustering method for genomic island detection in MRSA.
Date: November 16, 2017
Creator: Jani, Mehul; Sengupta, Soham; Hu, Kelsey & Azad, Rajeev K.
System: The UNT Digital Library
Bringing User-Centered Design to the Field of Language Archives (open access)

Bringing User-Centered Design to the Field of Language Archives

This article describes findings from a workshop that initiated a dialogue between the fields of user-centered design (UCD) and language archives.
Date: November 16, 2016
Creator: Wasson, Christina; Holton, Gary & Roth, Heather
System: The UNT Digital Library
Construct Validity of the Late-Life Function and Disability Instrument in African American Breast Cancer Survivors (open access)

Construct Validity of the Late-Life Function and Disability Instrument in African American Breast Cancer Survivors

Paper describes results of a study examining the validity of the Late-Life Function and Disability Instrument for cancer survivors, focusing specifically on African-American breast cancer survivors.
Date: November 16, 2016
Creator: Pandya, Ekta; Mistry, Jay; Dobhal, Megha; Borra, Sujana & Paxton, Raheem J.
System: The UNT Digital Library
Laser-Plasma Interactions in Drive Campaign targets on the National Ignition Facility (open access)

Laser-Plasma Interactions in Drive Campaign targets on the National Ignition Facility

None
Date: November 16, 2013
Creator: Hinkel, D. E.; Callahan, D. A.; Moody, J. D.; Amendt, P. A.; Lasinski, B. F.; MacGowan, B. J. et al.
System: The UNT Digital Library
Initial Results from the ANITA 2006-2007 Balloon Flight (open access)

Initial Results from the ANITA 2006-2007 Balloon Flight

We report initial results of the Antarctic Impulsive Transient Antenna (ANITA) 2006-2007 Long Duration Balloon flight, which searched for evidence of the flux of cosmogenic neutrinos. ANITA flew for 35 days looking for radio impulses that might be due to the Askaryan effect in neutrino-induced electromagnetic showers within the Antarctic ice sheets. In our initial high-threshold robust analysis, no neutrino candidates are seen, with no physics background. In a non-signal horizontal-polarization channel, we do detect 6 events consistent with radio impulses from extensive air showers, which helps to validate the effectiveness of our method. Upper limits derived from our analysis now begin to eliminate the highest cosmogenic neutrino models.
Date: November 16, 2011
Creator: Gorham, P. W.; Allison, P.; Barwick, S. W.; Beatty, J. J.; Besson, D. Z.; Binns, W. R. et al.
System: The UNT Digital Library
Nuclear energy density optimization: Large deformations (open access)

Nuclear energy density optimization: Large deformations

None
Date: November 16, 2011
Creator: Kortelainen, M.; McDonnell, J.; Nazarewicz, W.; Reinhard, P. G.; Sarich, J.; Schunck, N. et al.
System: The UNT Digital Library
Abstraction of Information From 2-  and 3-Dimensional Porflow Models Into a 1-D Goldsim Model - 11404 (open access)

Abstraction of Information From 2- and 3-Dimensional Porflow Models Into a 1-D Goldsim Model - 11404

The Savannah River National Laboratory has developed a 'hybrid' approach to Performance Assessment modeling which has been used for a number of Performance Assessments. This hybrid approach uses a multi-dimensional modeling platform (PorFlow) to develop deterministic flow fields and perform contaminant transport. The GoldSim modeling platform is used to develop the Sensitivity and Uncertainty analyses. Because these codes are performing complementary tasks, it is incumbent upon them that for the deterministic cases they produce very similar results. This paper discusses two very different waste forms, one with no engineered barriers and one with engineered barriers, each of which present different challenges to the abstraction of data. The hybrid approach to Performance Assessment modeling used at the SRNL uses a 2-D unsaturated zone (UZ) and a 3-D saturated zone (SZ) model in the PorFlow modeling platform. The UZ model consists of the waste zone and the unsaturated zoned between the waste zone and the water table. The SZ model consists of source cells beneath the waste form to the points of interest. Both models contain 'buffer' cells so that modeling domain boundaries do not adversely affect the calculation. The information pipeline between the two models is the contaminant flux. The domain …
Date: November 16, 2010
Creator: Taylor, G. & Hiergesell, R.
System: The UNT Digital Library
Development of Compton Radiography Diagnostics for Inertial Confinement Fusion Implosions (open access)

Development of Compton Radiography Diagnostics for Inertial Confinement Fusion Implosions

An important diagnostic tool for inertial confinement fusion will be time-resolved radiographic imaging of the dense cold fuel surrounding the hot spot. The measurement technique is based on point-projection radiography at photon energies from 60-200 keV where the Compton effect is the dominant contributor to the opacity of the fuel or pusher. We have successfully applied this novel Compton Radiography technique to the study of the final compression of directly driven plastic capsules at the OMEGA facility. The radiographs have a spatial and temporal resolution of {approx}10 {micro}m and {approx}10ps, respectively. A statistical accuracy of {approx}0.5% in transmission per resolution element is achieved, allowing localized measurements of areal mass densities to 7% accuracy. The experimental results show 3D non-uniformities and lower than 1D expected areal densities attributed to drive asymmetries and hydroinstabilities.
Date: November 16, 2010
Creator: Tommasini, R.; Hatchett, S. P.; Hey, D. S.; Izumi, N.; Koch, J. A.; Landen, O. L. et al.
System: The UNT Digital Library
Production of high brightness H- beam by charge exchange of hydrogen atom beam in sodium jet (open access)

Production of high brightness H- beam by charge exchange of hydrogen atom beam in sodium jet

Production of H{sup -} beam for accelerators applications by charge exchange of high brightness hydrogen neutral beam in a sodium jet cell is experimentally studied in joint BNL-BINP experiment. In the experiment, a hydrogen-neutral beam with 3-6 keV energy, equivalent current up to 5 A and 200 microsecond pulse duration is used. The atomic beam is produced by charge exchange of a proton beam in a pulsed hydrogen target. Formation of the proton beam is performed in an ion source by four-electrode multiaperture ion-optical system. To achieve small beam emittance, the apertures in the ion-optical system have small enough size, and the extraction of ions is carried out from the surface of plasma emitter with a low transverse ion temperature of {approx}0.2 eV formed as a result of plasma jet expansion from the arc plasma generator. Developed for the BNL optically pumped polarized ion source, the sodium jet target with recirculation and aperture diameter of 2 cm is used in the experiment. At the first stage of the experiment H{sup -} beam with 36 mA current, 5 keV energy and {approx}0.15 cm {center_dot} mrad normalized emittance was obtained. To increase H{sup -} beam current ballistically focused hydrogen neutral beam will …
Date: November 16, 2010
Creator: Davydenko, V.; Zelenski, A.; Ivanov, A. & Kolmogorov, A.
System: The UNT Digital Library
Spectroscopic Evidence for Exceptional Thermal Contribution to Electron-Beam Induced Fragmentation (open access)

Spectroscopic Evidence for Exceptional Thermal Contribution to Electron-Beam Induced Fragmentation

While electron beam induced fragmentation (EBIF) has been reported to result in the formation of nanocrystals of various compositions, the physical forces driving this phenomenon are still poorly understood. We report EBIF to be a much more general phenomenon than previously appreciated, operative across a wide variety of metals, semiconductors and insulators. In addition, we leverage the temperature dependent bandgap of several semiconductors to quantify -- using in situ cathodoluminescence spectroscopy -- the thermal contribution to EBIF, and find extreme temperature rises upwards of 1000K.
Date: November 16, 2010
Creator: Caldwell, Marissa A.; Haynor, Ben; Aloni, Shaul; Ogletree, D. Frank; Wong, H.-S. Philip; Urban, Jeffrey J. et al.
System: The UNT Digital Library
Teacher Efficacy as a Multigroup Model Using Latent Class Analysis (open access)

Teacher Efficacy as a Multigroup Model Using Latent Class Analysis

This article used Latent Class Analysis (LCA) to find that mathematics efficacy groups of preservice teachers vary based on where they were in their academic program.
Date: November 16, 2010
Creator: Eddy, Colleen & Easton-Brooks, Donald
System: The UNT Digital Library
Assessment of the Technologies for Molecular Biodosimetry for Human Low-Dose Radiation Exposure Symposium (open access)

Assessment of the Technologies for Molecular Biodosimetry for Human Low-Dose Radiation Exposure Symposium

Exposure to ionizing radiation produces few immediate outwardly-visible clinical signs, yet, depending on dose, can severely damage vital physiological functions within days to weeks and produce long-lasting health consequences among survivors. In the event of a radiological accident, the rapid evaluation of the individual absorbed dose is paramount to discriminate the worried but unharmed from those individuals who must receive medical attention. Physical, clinical and biological dosimetry are usually combined for the best dose assessment. However, because of the practical limits of physical and clinical dosimetry, many attempts have been made to develop a dosimetry system based on changes in biological parameters, including techniques for hematology, biochemistry, immunology, cytogenetics, etc. Lymphocyte counts and chromosome aberrations analyses are among the methods that have been routinely used for estimating radiation dose. However, these assays require several days to a week to be completed and therefore cannot be used to obtain a fast estimate of the dose during the first few days after exposure when the information would be most critical for identifying victims of radiation accidents who could benefit the most by medical intervention. The steadily increasing sophistication in our understanding of the early biochemical responses of irradiated cells and tissues provides …
Date: November 16, 2009
Creator: Coleman, Matthew A. (info: Ph.D.); Ramakrishnan, Narayani (info:Ph.D); Amundson, Sally A.; Tucker, James D. (info: Ph.D.); Dertinger, Stephen D. (info:Ph.D); Ossetrova, Natalia I. (info:Ph.D) et al.
System: The UNT Digital Library
Integrated Kinetic Simulation of Laser-Plasma Interactions, Fast-Electron Generation and Transport in Fast Ignition (open access)

Integrated Kinetic Simulation of Laser-Plasma Interactions, Fast-Electron Generation and Transport in Fast Ignition

We present new results on the physics of short-pulse laser-matter interaction of kilojoule-picosecond pulses at full spatial and temporal scale, using a new approach that combines a 3D collisional electromagnetic Particle-in-Cell code with an MHD-hybrid model of high-density plasma. In the latter, collisions damp out plasma waves, and an Ohm's law with electron inertia effects neglected determines the electric field. In addition to yielding orders of magnitude in speed-up while avoiding numerical instabilities, this allows us to model the whole problem in a single unified framework: the laser-plasma interaction at sub-critical densities, energy deposition at relativistic critical densities, and fast-electron transport in solid densities. Key questions such as the multi-picosecond temporal evolution of the laser energy conversion into hot electrons, the impact of return currents on the laser-plasma interaction, and the effect of self-generated electric and magnetic fields on electron transport will be addressed. We will report applications to current experiments.
Date: November 16, 2009
Creator: Kemp, A; Cohen, B & Divol, L
System: The UNT Digital Library
Modeling acid-gas generation from boiling chloride brines (open access)

Modeling acid-gas generation from boiling chloride brines

This study investigates the generation of HCl and other acid gases from boiling calcium chloride dominated waters at atmospheric pressure, primarily using numerical modeling. The main focus of this investigation relates to the long-term geologic disposal of nuclear waste at Yucca Mountain, Nevada, where pore waters around waste-emplacement tunnels are expected to undergo boiling and evaporative concentration as a result of the heat released by spent nuclear fuel. Processes that are modeled include boiling of highly concentrated solutions, gas transport, and gas condensation accompanied by the dissociation of acid gases, causing low-pH condensate. Simple calculations are first carried out to evaluate condensate pH as a function of HCl gas fugacity and condensed water fraction for a vapor equilibrated with saturated calcium chloride brine at 50-150 C and 1 bar. The distillation of a calcium-chloride-dominated brine is then simulated with a reactive transport model using a brine composition representative of partially evaporated calcium-rich pore waters at Yucca Mountain. Results show a significant increase in boiling temperature from evaporative concentration, as well as low pH in condensates, particularly for dynamic systems where partial condensation takes place, which result in enrichment of HCl in condensates. These results are in qualitative agreement with experimental …
Date: November 16, 2009
Creator: Zhang, Guoxiang; Spycher, Nicolas; Sonnenthal, Eric & Steefel, Carl
System: The UNT Digital Library
Muon-induced backgrounds in the CUORICINO experiment (open access)

Muon-induced backgrounds in the CUORICINO experiment

To better understand the contribution of cosmic ray muons to the CUORICINO background, ten plastic scintillator detectors were installed at the CUORICINO site and operated during 3 months of the CUORICINO experiment. From these measurements, an upper limit of 0.0021 counts/keV {center_dot} kg {center_dot} yr (95% C.L.) was obtained on the cosmic ray induced background in the neutrinoless double beta decay region of interest. The measurements were compared to Geant4 simulations, which are similar to those that will be used to estimate the backgrounds in CUORE.
Date: November 16, 2009
Creator: Andreotti, E.; Arnaboldi, C.; Avignone, F. T.; Balata, M.; Bandac, I.; Barucci, M. et al.
System: The UNT Digital Library
National Ignition Campaign Hohlraum Energetics (open access)

National Ignition Campaign Hohlraum Energetics

The first series of experiments on the National Ignition Facility (NIF) [E. I. Moses, R. N. Boyd, B. A. Remington, C. J. Keane, and R. Al-Ayat, 'The National Ignition Facility: ushering in a new age for high energy density science,' Phys. Plasmas 16, 041006 (2009)] tested ignition hohlraum 'energetics,' a term described by four broad goals: (1) Measurement of laser absorption by the hohlraum; (2) Measurement of the x-ray radiation flux (T{sub RAD}{sup 4}) on the surrogate ignition capsule; (3) Quantitative understanding of the laser absorption and resultant x-ray flux; and (4) Determining whether initial hohlraum performance is consistent with requirements for ignition. This paper summarizes the status of NIF hohlraum energetics experiments. The hohlraum targets and experimental design are described, as well as the results of the initial experiments. The data demonstrate low backscattered energy (< 10%) for hohlraums filled with helium gas. A discussion of our current understanding of NIF hohlraum x-ray drive follows, including an overview of the computational tools, i.e., radiation-hydrodynamics codes, that have been used to design the hohlraums. The performance of the codes is compared to x-ray drive and capsule implosion data from the first NIF experiments. These results bode well for future NIF …
Date: November 16, 2009
Creator: Meezan, N B; Atherton, L J; Callahan, D A; Dewald, E L; Dixit, S N; Dzenitis, E G et al.
System: The UNT Digital Library
Breast cancer by proxy: Can the microenvironment be both the cause and consequence? (open access)

Breast cancer by proxy: Can the microenvironment be both the cause and consequence?

Breast cancer is one of the most clear-cut examples of a solid tumor in which systemic cues play a decisive part in its development. The breast tissue is constantly subjected to changes in hormone levels and modifications in the microenvironment. This scenario is even more striking during tumor development because of the dramatic loss or aberration of basement membrane (BM) and myoepithelial cells and the gain of peritumoral myofibroblasts. We suggest that the microenvironment, defined here as all components of the mammary gland other than luminal and/or tumor epithelial cells, might be instrumental in maintaining organ integrity and in promoting, and at times even initiating, breast cancer development. As such, the tumor microenvironment and its constituents, alone or in combination, might serve as promising targets for therapy.
Date: November 16, 2008
Creator: Ronnov-Jessen, Lone & Bissell, Mina J
System: The UNT Digital Library
Commissioning Results of the LCLS Injector (open access)

Commissioning Results of the LCLS Injector

The Linac Coherent Light Source (LCLS) is a SASE xray Free-Electron Laser (FEL) project presently under construction at SLAC. The injector section, from drive-laser and RF photocathode gun through first bunch compressor chicane, was installed in fall 2006. Initial system commissioning with an electron beam has recently been completed. The second phase of construction, including second bunch compressor and full linac, is planned for 2008. In this paper, we report experimental results and experience gained during the first phase of machine commissioning. This includes the cathode, drive laser, RF photocathode gun, linac booster section, S-band and X-band RF systems, first bunch compressor, and the various beam diagnostics.
Date: November 16, 2007
Creator: Dowell, D. H.; Akre, R.; Ding, Y.; Emma, P.; Frisch, J.; Gilevich, S. et al.
System: The UNT Digital Library
CORROSION OF LEAD SHIELDING IN NUCLEAR MATERIALS PACKAGES (open access)

CORROSION OF LEAD SHIELDING IN NUCLEAR MATERIALS PACKAGES

Inspection of United States-Department of Energy (US-DOE) model 9975 nuclear materials shipping package revealed corrosion of the lead shielding induced by off-gas constituents from organic components in the package. Experiments were performed to determine the corrosion rate of lead when exposed to off-gas or degradation products of these organic materials. The results showed that the room temperature vulcanizing (RTV) sealant was the most corrosive organic species followed by the polyvinyl acetate (PVAc) glue. The fiberboard material induced corrosion to a much lesser extent than the PVAc glue and RTV, and only in the presence of condensed water. The results indicated faster corrosion at temperatures higher than ambient and with condensed water as expected. A corrosion rate of 0.05 mm/year measured for coupons exposed to the most aggressive conditions was recommended as a conservative estimate for use in package performance calculations.
Date: November 16, 2007
Creator: Subramanian, K & Kerry Dunn, K
System: The UNT Digital Library