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Mechanical and Rheological Properties of Bamboo Pulp Fiber Reinforced High Density Polyethylene Composites: Influence of Nano CaCO3 Treatment and Manufacturing Process with Different Pressure Ratings (open access)

Mechanical and Rheological Properties of Bamboo Pulp Fiber Reinforced High Density Polyethylene Composites: Influence of Nano CaCO3 Treatment and Manufacturing Process with Different Pressure Ratings

Article investigating the effect of the relative motion of nano CaCO3 reinforced bamboo pulp fiber (BPF)/HDPE composite components on the mechanical performance.
Date: August 17, 2021
Creator: Wang, Cuicui; Wei, Xin; Smith, Lee M.; Wang, Ge; Zhang, Shuangbao & Cheng, Haitao
System: The UNT Digital Library
Formation and Photoinduced Electron Transfer in Porphyrin- and Phthalocyanine-Bearing N-Doped Graphene Hybrids Synthesized by Click Chemistry (open access)

Formation and Photoinduced Electron Transfer in Porphyrin- and Phthalocyanine-Bearing N-Doped Graphene Hybrids Synthesized by Click Chemistry

Article presents research where N-doped graphene (NG) has been covalently decorated with porphyrin and phthalocyanine moieties using click chemistry. Evidence of charge separation in these hybrids is secured from femtosecond transient absorption studies, acting NG as electron acceptor.
Date: March 7, 2022
Creator: Arellano, Luis M.; Gobeze, Habtom B.; Barrejón, Myriam; Parejo, Concepción; Álvarez, Julio C.; Gómez-Escalonilla, María J. et al.
System: The UNT Digital Library
The Roles of Individual and Psychosocial Factors in Predicting Quality of Life Among Working Women in Shanghai (open access)

The Roles of Individual and Psychosocial Factors in Predicting Quality of Life Among Working Women in Shanghai

Paper describes study aiming to investigate the roles of individual factors, particularly age, in addition to occupational stress and burnout on quality of life for working women in Shanghai, China.
Date: March 7, 2020
Creator: Xiao, Yi; Zhang, Tao; Gu, Xiangli; Lee, Joonyoung & Wang, Hongying
System: The UNT Digital Library
Divertor Target Heat Load Reduction by Electrical Biasing, and Application to COMPASS-D (open access)

Divertor Target Heat Load Reduction by Electrical Biasing, and Application to COMPASS-D

A toroidally-asymmetric potential structure in the scrape-off layer (SOL) plasma may be formed by toroidally distributed electrical biasing of the divertor target tiles. The resulting ExB convective motions should increase the plasma radial transport in the SOL and thereby reduce the heat load at the divertor [1]. In this paper we develop theoretical modeling and describe the implementation of this concept to the COMPASS-D divertor. We show that strong magnetic shear near the X-point should cause significant squeezing of the convective cells preventing convection from penetrating above the X-point. This should result in reduced heat load at the divertor target without increasing the radial transport in the portion of the SOL in direct contact with the core plasma, potentially avoiding any confinement degradation. implementation of divertor biasing is in hand on COMPASS-D involving insulation of, and modifications to, the present divertor tiles. Calculations based on measured edge parameters suggest that modest currents {approx} 8 A/tile are required, at up to 150V, to drive the convection. A technical test is preceeding full bias experiments.
Date: March 7, 2001
Creator: Fielding, S. J.; Cohen, R. H.; Helander, P. & Ryutov, D. D.
System: The UNT Digital Library
Nondestructive evaluation and assay for the plutonium ceramification test facility (open access)

Nondestructive evaluation and assay for the plutonium ceramification test facility

Lawrence Livermore National Laboratory (LLNL) has conducted design and testing activities of the Nondestructive Assay/Evaluation (NDA/NDE) system that will be installed to support the Plutonium Ceramification Test Facility (PuCTF). PuCTF immobilizes plutonium using the ceramic can-in-canister technology. The overall function of the NDA/NDE System is to ensure that sintered pucks contain the appropriate materials for ceramification process control, special nuclear materials (SNM) accountability, and repository acceptance. The system accepts sample pucks from the ceramification system, performs measurements, and determines if the product pucks are acceptable. This report details the conceptual system that is being developed.
Date: March 7, 2000
Creator: Mitchell, M.; Pugh, D. & Wang, T. F.
System: The UNT Digital Library
Delta/Alpha-Prime Phase Transformations in a Pu-Ga Alloy (open access)

Delta/Alpha-Prime Phase Transformations in a Pu-Ga Alloy

In pure plutonium, the monoclinic {alpha} phase is the equilibrium phase at ambient temperature and pressure. The addition of a few percent of gallium, however, allows the fcc {delta} phase to be retained metastablely at ambient conditions. When the metastable {delta} phase is cooled to subambient temperatures, it partially transforms to the monoclinic {alpha}' phase, which has gallium supersaturated in the lattice. The {alpha}' phase reverts to the {delta} phase when the sample is heated above the ambient temperature. The martensite burst (M{sub b}) and reversion start (R{sub s}) temperatures are functions of the composition, heating rate, and prior thermal history. For a Pu-2.0 at% Ga alloy, the transformation hysteresis is approximately 150 C, which is large compared with other solid-solid phase transformations. Both the forward and reverse transformations are martensitic and proceed via a burst mode. Here, we use differential scanning calorimetry (DSC) and resistometry to perform fundamental studies of the {alpha}'/{delta} transformations with the goal of understanding how aging may affect {delta} phase stability, particularly the M{sub b} temperature. Because materials properties of the {alpha}' and {delta} phases are considerably different (including a density increase of 25% and an accompanying resistivity increase of 46% upon transformation from {delta} …
Date: March 7, 2005
Creator: Blobaum, K M; Krenn, C R; Wall, M A & Schwartz, A J
System: The UNT Digital Library
Type 1 Frequency Doubling at 1064 nm in LaCa40(B03)3 (LaCOB), GdCa40(B03)3(GdCOB), and YCa40(B03)3(YCOB) (open access)

Type 1 Frequency Doubling at 1064 nm in LaCa40(B03)3 (LaCOB), GdCa40(B03)3(GdCOB), and YCa40(B03)3(YCOB)

We have grown and characterized LaCOB, a new member to the GdCOB family of nonlinear crystals. LaCOB has a d{sub eff} of 0.52 {plus_minus} 0.05 pm/V and an angular sensitivity of 1224 {plus_minus} 184 (cm-rad){sup -1} for type I frequency doubling at 1064 nm. The d{sub {alpha}{beta}{beta}} and d{sub {gamma}{beta}{beta}} coefficients of the nonlinear optical tensor for LaCOB, GdCOB, and YCOB were determined to have values of {vert_bar}0.26 {plus_minus} 0.04{vert_bar} pm/V and |1.69 {plus_minus} 0.17| pm/V, respectively. Results of phase-matching angle measurements at 1064 nm and 1047 nm predict LaCOB to be non-critically phase-matched (NCPM) at 1042 {plus_minus} 1.5 nm. We also estimate the thermal sensitivity of LaCOB to be less than 0.1 (cm- C){sup -1}.
Date: March 7, 2001
Creator: Adams, J. J.; Ebbers, C. A.; Schaffers, K. I. & Payne, S. A.
System: The UNT Digital Library
Crystal stability and equation of state for americium: theory (open access)

Crystal stability and equation of state for americium: theory

None
Date: March 7, 2005
Creator: Soderlind, P & Landa, A
System: The UNT Digital Library
Characterization of a picosecond laser generated 4.5 keV Ti K-alpha source for pulsed radiography (open access)

Characterization of a picosecond laser generated 4.5 keV Ti K-alpha source for pulsed radiography

None
Date: March 7, 2005
Creator: King, J A; Key, M H; Chen, C D; Freeman, R R; Phillips, T; Akli, K U et al.
System: The UNT Digital Library
Activation of the Mercury Laser: A Diode-Pumped Solid-State Laser Driver for Inertial Fusion (open access)

Activation of the Mercury Laser: A Diode-Pumped Solid-State Laser Driver for Inertial Fusion

Initial measurements are reported for the Mercury laser system, a scalable driver for rep-rated high energy density physics research. The performance goals include 10% electrical efficiency at 10 Hz and 100 J with a 2-10 ns pulse length. This laser is an angularly multiplexed 4-pass gas-cooled amplifier system based on image relaying to minimize wavefront distortion and optical damage risk at the 10 Hz operating point. The efficiency requirements are fulfilled using diode laser pumping of ytterbium doped strontium fluorapatite crystals.
Date: March 7, 2001
Creator: Bayramian, A. J.; Bibeau, C.; Beach, R. J.; Chanteloup, J. C.; Ebbers, C. A.; Kanz, K. et al.
System: The UNT Digital Library
Direct Carbon Conversion: Application to the Efficient Conversion of Fossil Fuels to Electricity (open access)

Direct Carbon Conversion: Application to the Efficient Conversion of Fossil Fuels to Electricity

We introduce a concept for efficient conversion of fossil fuels to electricity that entails the decomposition of fossil-derived hydrocarbons into carbon and hydrogen, and electrochemical conversion of these fuels in separate fuel cells. Carbon/air fuel cells have the advantages of near zero entropy change and associated heat production (allowing 100% theoretical conversion efficiency). The activities of the C fuel and CO{sub 2} product are invariant, allowing constant EMF and full utilization of fuel in single pass mode of operation. System efficiency estimates were conducted for several routes involving sequential extraction of a hydrocarbon from the fossil resource by (hydro) pyrolysis followed by thermal decomposition. The total energy conversion efficiencies of the processes were estimated to be (1) 80% for direct conversion of petroleum coke; (2) 67% HHV for CH{sub 4}; (3) 72% HHV for heavy oil (modeled using properties of decane); (4) 75.5% HHV (83% LHV) for natural gas conversion with a Rankine bottoming cycle for the H{sub 2} portion; and (5) 69% HHV for conversion of low rank coals and lignite through hydrogenation and pyrolysis of the CH{sub 4} intermediate. The cost of carbon fuel is roughly $7/GJ, based on the cost of the pyrolysis step in the industrial …
Date: March 7, 2001
Creator: Cooper, J. F.; Cherepy, N.; Berry, G.; Pasternak, A.; Surles, T. & Steinberg, M.
System: The UNT Digital Library
Role of Fusion Energy in a Sustainable Global Energy Strategy (open access)

Role of Fusion Energy in a Sustainable Global Energy Strategy

Fusion energy is one of only a few truly long-term energy options. Since its inception in the 1950s, the vision of the fusion energy research program has been to develop a viable means of harnessing the virtually unlimited energy stored in the nuclei of light atoms--the primary fuel deuterium is present as one part in 6,500 of all hydrogen. This vision grew out of the recognition that the immense power radiated by the sun is fueled by nuclear fusion in its hot core. Such high temperatures are a prerequisite for driving significant fusion reactions. The fascinating fourth state of matter at high temperatures is known as plasma. It is only in this fourth state of matter that the nuclei of two light atoms can fuse, releasing the excess energy that was needed to separately bind each of the original two nuclei. Because the nuclei of atoms carry a net positive electric charge, they repel each other. Hydrogenic nuclei, such as deuterium and tritium, must be heated to approximately 100 million degrees Celsius to overcome this electric repulsion and fuse. There have been dramatic recent advances in both the scientific understanding of fusion plasmas and in the generation of fusion power …
Date: March 7, 2001
Creator: Meier, Wayne; Najmabadi, Farokh; Schmidt, John & Sheffield, John
System: The UNT Digital Library
Opting Out: Parents Creating Contested Spaces to Challenge Standardized Tests (open access)

Opting Out: Parents Creating Contested Spaces to Challenge Standardized Tests

This article explores how the opt-out movement has responded to the combination of a stringent federal policy with weak and often variable implementation among the states.
Date: March 7, 2016
Creator: Mitra, Dana; Mann, Bryan & Hlavacik, Mark
System: The UNT Digital Library
Improved system for perpendicular electron-cyclotron emission measurements on TMX-Upgrade (open access)

Improved system for perpendicular electron-cyclotron emission measurements on TMX-Upgrade

Perpendicular electron-cyclotron emission (PECE) is used on TMX-U to diagnose thermal-barrier hot electrons (T/sub H/ approx. 100 to 400 keV); yielding the time history of the temperature of these relativistic electrons. We describe an improved quasi-optical viewing system for these measurements that uses high sensitivity superheterodyne receivers at fixed frequencies of 60, 98, 130, and 196 GHz. The improved viewing and transport system consists of an off-axis ellipsoidal mirror that images the plasma onto a V-band conical collection horn, an overmoded circular waveguide (7/8'' diam) that transports the radiation outside the vacuum vessel where the polarization is selected, and a high absorptivity Macor beam dump to prevent internal wall reflections from entering the viewing system. A relativistic code is used to calculate optically thin PECE signals from relativistic electrons for various energy and pitch angle distributions. 4 refs., 4 figs.
Date: March 7, 1986
Creator: Lasnier, C. J.; Ellis, R. F. & James, R. A.
System: The UNT Digital Library
Resolvability of positron decay channels (open access)

Resolvability of positron decay channels

Many data analysis treatments of positron experiments attempt to resolve two or more positron decay or exist channels which may be open simultaneously. Examples of the need to employ such treatments of the experimental results can be found in the resolution of the constituents of a defect ensemble, or in the analysis of the complex spectra which arise from the interaction of slow positrons at or near the surfaces of solids. Experimental one- and two-dimensional angular correlation of annihilation radiation experiments in Al single crystals have shown that two defect species (mono- and divacancies) can be resolved under suitable conditions. Recent experiments at LLNL indicate that there are a variety of complex exit channels open to positrons interacting at surfaces, and ultimely these decay channels must also be suitably resolved from one another. 6 refs., 4 figs.
Date: March 7, 1985
Creator: Fluss, M.J.; Howell, R.H.; Rosenberg, I.J. & Meyer, P.
System: The UNT Digital Library
Proof of Principle Experiments That Demonstrate Utility of Cocktail Hohlraums for Indirect Drive Ignition (open access)

Proof of Principle Experiments That Demonstrate Utility of Cocktail Hohlraums for Indirect Drive Ignition

None
Date: March 7, 2007
Creator: Jones, O. S.; Schein, J.; Rosen, M.. D.; Suter, L. J.; Wallace, R. J.; Dewald, E. L. et al.
System: The UNT Digital Library
Underwater Blast Experiments and Modeling for Shock Mitigation (open access)

Underwater Blast Experiments and Modeling for Shock Mitigation

A simple but novel mitigation concept to enforce standoff distance and reduce shock loading on a vertical, partially-submerged structure is evaluated using scaled aquarium experiments and numerical modeling. Scaled, water tamped explosive experiments were performed using three gallon aquariums. The effectiveness of different mitigation configurations, including air-filled media and an air gap, is assessed relative to an unmitigated detonation using the same charge weight and standoff distance. Experiments using an air-filled media mitigation concept were found to effectively dampen the explosive response of the aluminum plate and reduce the final displacement at plate center by approximately half. The finite element model used for the initial experimental design compares very well to the experimental DIC results both spatially and temporally. Details of the experiment and finite element aquarium models are described including the boundary conditions, Eulerian and Lagrangian techniques, detonation models, experimental design and test diagnostics.
Date: March 7, 2010
Creator: Glascoe, L; McMichael, L; Vandersall, K & Margraf, J
System: The UNT Digital Library
B, D and K Decays (open access)

B, D and K Decays

The present report documents the results of Working Group 2: B, D and K decays, of the workshop on Flavor in the Era of the LHC, held at CERN from November 2005 through March 2007. With the advent of the LHC, we will be able to probe New Physics (NP) up to energy scales almost one order of magnitude larger than it has been possible with present accelerator facilities. While direct detection of new particles will be the main avenue to establish the presence of NP at the LHC, indirect searches will provide precious complementary information, since most probably it will not be possible to measure the full spectrum of new particles and their couplings through direct production. In particular, precision measurements and computations in the realm of flavor physics are expected to play a key role in constraining the unknown parameters of the Lagrangian of any NP model emerging from direct searches at the LHC. The aim of Working Group 2 was twofold: on one hand, to provide a coherent, up-to-date picture of the status of flavor physics before the start of the LHC; on the other hand, to initiate activities on the path towards integrating information on NP …
Date: March 7, 2008
Creator: Artuso, M.; Asner, D. M.; Ball, P.; Baracchini, E.; Bell, G.; Beneke, M. et al.
System: The UNT Digital Library
Structures in Molecular Clouds: Modeling (open access)

Structures in Molecular Clouds: Modeling

None
Date: March 7, 2006
Creator: Kane, J. O.; Ryutov, D. D.; Remington, B. A.; Pound, M. & Mizuta, A.
System: The UNT Digital Library
Applications of Lagrangian Dispersion Modeling to the Analysis of Changes in the Specific Absorption of Elemental Carbon (open access)

Applications of Lagrangian Dispersion Modeling to the Analysis of Changes in the Specific Absorption of Elemental Carbon

We use a Lagrangian dispersion model driven by a mesoscale model with four-dimensional data assimilation to simulate the dispersion of elemental carbon (EC) over a region encompassing Mexico City and its surroundings, the study domain for the 2006 MAX-MEX experiment, which was a component of the MILAGRO campaign. The results are used to identify periods when biomass burning was likely to have had a significant impact on the concentrations of elemental carbon at two sites, T1 and T2, downwind of the city, and when emissions from the Mexico City Metropolitan Area (MCMA) were likely to have been more important. They are also used to estimate the median ages of EC affecting the specific absorption of light, aABS, at 870 nm as well as to identify periods when the urban plume from the MCMA was likely to have been advected over T1 and T2. Values of aABS at T1, the nearer of the two sites to Mexico City, were smaller at night and increased rapidly after mid-morning, peaking in the mid-afternoon. The behavior is attributed to the coating of aerosols with substances such as sulfate or organic carbon during daylight hours, but such coating appears to be limited or absent at …
Date: March 7, 2008
Creator: Doran, J. C.; Fast, Jerome D.; Barnard, James C.; Laskin, Alexander; Desyaterik, Yury; Gilles, Marry K. et al.
System: The UNT Digital Library
Collider Aspects of Flavour Physics at High Q (open access)

Collider Aspects of Flavour Physics at High Q

This chapter of the report of the 'Flavour in the era of LHC' workshop discusses flavor related issues in the production and decays of heavy states at LHC, both from the experimental side and from the theoretical side. We review top quark physics and discuss flavor aspects of several extensions of the Standard Model, such as supersymmetry, little Higgs model or models with extra dimensions. This includes discovery aspects as well as measurement of several properties of these heavy states. We also present public available computational tools related to this topic.
Date: March 7, 2008
Creator: del Aguila, F.; Aguilar-Saavedra, J. A.; Allanach, B. C.; Alwall, J.; Andreev, Yu.; Aristizabal Sierra, D. et al.
System: The UNT Digital Library
Using Higher Order Modes in Superconducting Accelerating Cavities for Beam Monitoring (open access)

Using Higher Order Modes in Superconducting Accelerating Cavities for Beam Monitoring

Dipole modes have been shown to be successful diagnostics for the beam position in superconducting accelerating cavities at the Free Electron Laser in Hamburg (FLASH) facility at DESY. By help of downmixing electronics the signals from the two higher order mode (HOM) couplers mounted on each cavity are monitored. The calibration, based on singular value decomposition, is more complicated than in standard position monitors. Position like signals based on this calibration are currently being in the process of being included in the control system. A second setup based on digitizing the spectrum from the HOM couplers has been used for monitoring monopole modes. The beam phase with respect to the RF has been thus monitored. The position calibration measurements and phase monitoring made at the FLASH are presented.
Date: March 7, 2008
Creator: Molloy, S.; Baboi, N.; Eddy, N.; Frisch, J.; Hendrickson, L.; Hensler, O. et al.
System: The UNT Digital Library
Development and Implementation of an Ergonomics Program for Research Laboratories (open access)

Development and Implementation of an Ergonomics Program for Research Laboratories

None
Date: March 7, 2006
Creator: Roberts, T.; Yu, E. & Herbert, R.
System: The UNT Digital Library
Hawaii Geothermal Project Environmental Impact Statement Scoping Meetings. Volume 2 (open access)

Hawaii Geothermal Project Environmental Impact Statement Scoping Meetings. Volume 2

None
Date: March 7, 1992
Creator: unknown
System: The UNT Digital Library