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Temperature dependent rate coefficients for the gas-phase OH + Furan-2,5-dione (C4H2O3, maleic anhydride) reaction (open access)

Temperature dependent rate coefficients for the gas-phase OH + Furan-2,5-dione (C4H2O3, maleic anhydride) reaction

Authors of the article assert that rate coefficients, k1(T), for the gas-phase reaction of the OH radical with Furan-2,5-dione (maleic anhydride (MA), C4H2O3), a biomass burning related compound, were measured under pseudo first-order conditions in OH using the pulsed laser photolysis - laser induced fluorescence method over a range of temperature and bath gas pressure. Their results are compared with a previous room temperature relative rate study of the OH + MA reaction and significant discrepancy between the studies is discussed. This is the accepted manuscript version of the published article.
Date: May 30, 2020
Creator: Chattopadhyay, Aparajeo; Papadimitriou, Vassileios C.; Marshall, Paul & Burkholder, James B. (James Bart), 1954-
System: The UNT Digital Library
Investigation of a Consumer’s Purchase Intentions and Behaviors towards Environmentally Friendly Grocery Packaging (open access)

Investigation of a Consumer’s Purchase Intentions and Behaviors towards Environmentally Friendly Grocery Packaging

Article asserts that plastic packaging dominates the US grocery industry, which raises the question of whether consumers are purchasing food that is not wrapped in conventional plastic but environmentally friendly packaging. Through their study, the authors hope that their findings provide marketers with fresh insights into the characteristics of consumers willing to purchase grocery items packaged in environmentally friendly materials.
Date: May 30, 2023
Creator: Oliver, Mikah O.; Jestratijevic, Iva; Uanhoro, James & Knight, Dee K.
System: The UNT Digital Library
NRPreTo: A Machine Learning-Based Nuclear Receptor and Subfamily Prediction Tool (open access)

NRPreTo: A Machine Learning-Based Nuclear Receptor and Subfamily Prediction Tool

Article asserts that the nuclear receptor (NR) superfamily includes phylogenetically related ligand-activated proteins, which play a key role in various cellular activities. The authors developed Nuclear Receptor Prediction Tool (NRPreTo), a two-level NR prediction tool with a unique training approach where in addition to the sequence-based features used by existing NR prediction tools, six additional feature groups depicting various physiochemical, structural, and evolutionary features of proteins were utilized.
Date: May 30, 2023
Creator: Madugula, Sita Sirisha; Pandey, Suman; Amalapurapu, Shreya & Bozdag, Serdar
System: The UNT Digital Library
Breeding strategies of open-cup-nesting birds in sub-Antarctic forests of Navarino Island, Chile (open access)

Breeding strategies of open-cup-nesting birds in sub-Antarctic forests of Navarino Island, Chile

Article describing the breeding strategies (i.e., nest dimensions, nest height from the ground, egg laying rhythm, clutch size, length of the developmental periods, breeding phenology, and diversity of nesting substrate) of five passerine birds that inhabit sub-Antarctic ecosystems.
Date: November 20, 2018
Creator: Jara, Rocío Fernanda; Crego, Ramiro D.; Arellano, Francisco Javier; Altamirano, Tomás A.; Ibarra, J. Tomás; Rozzi, Ricardo, 1960- et al.
System: The UNT Digital Library
Cooperative MPC&A Enhancements at Russian Navy Sites (open access)

Cooperative MPC&A Enhancements at Russian Navy Sites

U.S. MPC&A cooperation with the Russian Federation (RF) Navy is based on a Joint Statement signed in 1996 to protect Highly Enriched Uranium (HEU) fresh fuel used for nuclear propulsion. The Russian Federation Navy is the largest owner in Russia of highly enriched uranium, both in the form of fresh nuclear fuel, and in the form of slightly irradiated fuel with a long cooling time after irradiation. As a result of this agreement, projects began at the Northern Fleet Fresh Fuel Storage Facility (Site 49) and Refueling Ship PM-63. Initial projects provided upgrades for RF Navy HEU fresh fuel storage facilities, beginning with a land-based facility near Murmansk and later adding other land-based and ship-based fresh fuel storage facilities. Additional protocols (December 1997, January 1999, and March 2000) significantly expanded cooperation to include all HEU fuel under RF Navy control. To date, it is estimated that tens of metric tons of HEU have been secured - enough to construct hundreds of nuclear devices. It was determined that the cooperation would be coordinated by the Russian Research Center, Kurchatov Institute. This paper describes the history of the Program development, its stages, current status, scale of the work and prospects.
Date: May 30, 2001
Creator: Nelson, N. N.; O'Shell, P.; Hendrickson, S.; Sukhoruchkin, V.; Antipov, S.; Melkhov, E. et al.
System: The UNT Digital Library
A 2-Liter, 2000 MPa Air Source for the Radiatively Driven Hypersonic Wind Tunnel (open access)

A 2-Liter, 2000 MPa Air Source for the Radiatively Driven Hypersonic Wind Tunnel

The A2 LITE is a 2 liter, 2000 MPa, 750 K ultra-high pressure (UHP) vessel used to demonstrate UHP technology and to provide an air flow for wind tunnel nozzle development. It is the largest volume UHP vessel in the world. The design is based on a 100:1 pressure intensification using a hydraulic ram as a low pressure driver and a three-layer compound cylinder UHP section. Active control of the 900 mm piston stroke in the 63.5 mm bore permits pressure-time profiles ranging from static to constant pressure during flow through a 1 mm throat diameter nozzle for 1 second.
Date: May 30, 2002
Creator: Costantino, M & Lofftus, D
System: The UNT Digital Library
Keck Adaptive Optics Observations of TW Hydrae Association Members (open access)

Keck Adaptive Optics Observations of TW Hydrae Association Members

Adaptive optics (AO) on 8-10 m telescopes is an enormously powerful tool for studying young nearby stars. It is especially useful for searching for companions. Using AO on the 10-m W.M. Keck II telescope we have measured the position of the brown dwarf companion to TWA5 and resolved the primary into an 0.055{double_prime} double. Over the next several years follow-up astrometry should permit an accurate determination of the masses of these young stars. We have also re-observed the candidate extrasolar planet TWAGB, but measurements of its motion relative to TWA6A are inconclusive. We are carrying out a search for new planetary or brown dwarf companions to TWA stars and, if current giant planet models are correct, are currently capable of detecting a 1 Jupiter-mass companion at {approx} 1.0{double_prime} and a 5 Jupiter-mass companion at {approx} 0.5{double_prime} around a typical TWA member.
Date: May 30, 2001
Creator: Macintosh, B; Max, C; Zuckerman, B; Becklin, E E; Kaisler, D; Lowrance, P et al.
System: The UNT Digital Library
Electrochemical Behavior of Alloy 22 in 5 M CaC12 (open access)

Electrochemical Behavior of Alloy 22 in 5 M CaC12

The corrosion resistance of Alloy 22 (UNS No.: N06022) was studied in 5 M CaCl{sub 2} electrolyte at various temperatures. Potentiodynamic polarization was used to examine the electrochemical behavior and measure the key potentials. Alloy 22 was found to be susceptible to localized corrosion in this high chloride [10M Cl{sup -}] environment at temperatures as low as 6O C.
Date: May 30, 2002
Creator: Ilevbare, G O
System: The UNT Digital Library
Shock Propagation and Instability Structures in Compressed Silica Aerogels (open access)

Shock Propagation and Instability Structures in Compressed Silica Aerogels

We have performed a series of experiments examining shock propagation in low density aerogels. High-pressure ({approx}100 kbar) shock waves are produced by detonating high explosives. Radiography is used to obtain a time sequence imaging of the shocks as they enter and traverse the aerogel. We compress the aerogel by impinging shocks waves on either one or both sides of an aerogel slab. The shock wave initially transmitted to the aerogel is very narrow and flat, but disperses and curves as it propagates. Optical images of the shock front reveal the initial formation of a hot dense region that cools and evolves into a well-defined microstructure. Structures observed in the shock front are examined in the framework of hydrodynamic instabilities generated as the shock traverses the low-density aerogel. The primary features of shock propagation are compared to simulations, which also include modeling the detonation of the high explosive, with a 2-D Arbitrary Lagrange Eulerian hydrodynamics code The code includes a detailed thermochemical equation of state and rate law kinetics. We will present an analysis of the data from the time resolved imaging diagnostics and form a consistent picture of the shock transmission, propagation and instability structure.
Date: May 30, 2002
Creator: Howard, W. M.; Molitoris, J. D.; DeHaven, M. R.; Gash, A. E. & Satcher, J. H.
System: The UNT Digital Library
Carcinogens formed when Meat is Cooked (open access)

Carcinogens formed when Meat is Cooked

Diet has been associated with varying cancer rates in human populations for many years, yet the causes of the observed variation in cancer patterns have not been adequately explained (Wynder et al. 1977). Along with the effect of diet on human cancer incidence is the strong evidence that mutations are the initiating events in the cancer process (Vogelstein et al. 1992). Foods, when heated, are a good source of genotoxic carcinogens that very likely are a cause for some of these events(Doll et al. 1981). These carcinogens fall into two chemical classes: heterocyclic aromatic amines (HAA) and polycyclic aromatic hydrocarbons (PAH). There is ample evidence that many of these compounds are complete carcinogens in rodents(El-Bayoumy et al. 1995; Ohgaki et al. 1991). Heterocyclic aromatic amines are among the most potent mutagenic substances ever tested in the Ames/Salmonella mutagenicity test (Wakabayashi et al. 1992). Both classes of carcinogen cause tumors in rodents at multiple sites, (El-Bayoumy et al. 1995; Ohgaki et al. 1991) many of which are common tumor sites in people on a Western diet. An HAA, PhIP (2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine), and a PAH, B[a]P (benzo[a]pyrene), of comparable carcinogenic potency caused mammary gland tumors in a feeding study in female rats (El-Bayoumy …
Date: May 30, 2003
Creator: Felton, J S; Salmon, C P & Knize, M G
System: The UNT Digital Library
Mechanical Properties and Corrosion Characteristics of Thermally Aged Alloy 22 (open access)

Mechanical Properties and Corrosion Characteristics of Thermally Aged Alloy 22

Alloy 22 (UNS N06022) is a candidate material for the external wall of the high level nuclear waste containers for the potential repository site at Yucca Mountain. In the mill-annealed (MA) condition, Alloy 22 is a single face centered cubic phase. When exposed to temperatures on the order of 600 C and above for times higher than 1 h, this alloy may develop secondary phases that reduce its mechanical toughness and corrosion resistance. The objective of this work was to age Alloy 22 at temperatures between 482 C and 760 C for times between 0.25 h and 6,000 h and to study the mechanical and corrosion performance of the resulting material. Aging was carried out using wrought specimens as well as gas tungsten arc welded (GTAW) specimens. Mechanical and corrosion testing was carried out using ASTM standards. Results show-that the higher the aging temperature and the longer the aging time, the lower the impact toughness of the aged material and the lower its corrosion resistance. However, extrapolating both mechanical and corrosion laboratory data predicts that Alloy 22 will remain corrosion resistant and mechanically robust for the projected lifetime of the waste container.
Date: May 30, 2002
Creator: Rebak, R B & Crook, P
System: The UNT Digital Library
The Kinetic Stabilizer: A Route to Simpler Tandem Mirror Systems? (open access)

The Kinetic Stabilizer: A Route to Simpler Tandem Mirror Systems?

This paper discusses a new approach to an MHD stabilizing technique for magnetic fusion systems of the axisymmetric ''open-ended'' variety. The concept is adaptable to tandem-mirror systems and would result in a major simplification of such systems, accompanied by a substantial improvement in their confinement characteristics, The paper first discusses the present impetus to find a simpler and less expensive route to fusion than that offered by the mainline approach, the tokamak. The history of magnetic fusion research shows that closed and open systems exhibit very different confinement characteristics. Closed systems, such as the tokamak, the stellarator, or the reversed-field pinch have cross-field transport that is dominated by plasma turbulence. By contrast, there are examples of open-systems where turbulence, if present at all, was at such low levels that the transport agreed with ''classical'' predictions. The clearest examples are ones in which the field geometry was axiymmetric. However axisymmetric mirror systems are subject to MHD instability. Thus in the years following the famous Ioffe experiment, most open systems have employed asymmetric magnetic fields, with attendant problems of complexity and enhanced cross-field transport. This paper proposes a new means of stabilizing axisymmetric mirror-based systems. The idea, called the ''Kinetic Stabilizer'' has …
Date: May 30, 2001
Creator: Post, R
System: The UNT Digital Library
Effect of Insolation Boundary Conditions on Type B Package Internal Temperatures (open access)

Effect of Insolation Boundary Conditions on Type B Package Internal Temperatures

The prescription of the initial conditions and the final conditions for a thermal accident for Type B packages are different for differing regulations. This paper presents an analytical method for estimating the effect of the boundary conditions on post-fire peak internal package temperatures. Results are given for several boundary conditions for a Type B drum-type package.
Date: May 30, 2002
Creator: Hovingh, J & Shah, VL
System: The UNT Digital Library
Characterization of the Resistance of Alloy 22 to Stress Corrosion Cracking (open access)

Characterization of the Resistance of Alloy 22 to Stress Corrosion Cracking

In its current design, the high-level nuclear waste containers include an external layer of Alloy 22 (Ni-22Cr-13Mo-3W-3Fe). Since over their lifetime, the containers may be exposed to multi-ionic aqueous environments, a potential degradation mode of the outer layer could be environmentally assisted cracking (EAC). The objective of the current research was to characterize the effect of applied potential and temperature on the susceptibility of Alloy 22 to EAC in simulated concentrated water (SCW) using the slow strain rate test (SSRT). Results show that Alloy 22 may suffer EAC at applied potentials approximately 400 mV more anodic than the corrosion potential (E{sub corr}).
Date: May 30, 2002
Creator: King, K. J.; Estill, J. C. & Rebak, R. B.
System: The UNT Digital Library
MAJOR GCFR DESIGN CHANGES (open access)

MAJOR GCFR DESIGN CHANGES

None
Date: May 30, 1980
Creator: Schoene, T.; Hansen, R. & Menzel, H.
System: The UNT Digital Library
Subnanosecond trigger system for ETA (open access)

Subnanosecond trigger system for ETA

A high-voltage trigger system capable of triggering 30, 250 kV spark gaps; each with less than +- 1 ns jitter has been constructed. In addition to low jitter rates, the trigger system must be capable of delivering the high voltage pulses to the spark gaps either simultaneously or sequentially as determined by other system requirements. The trigger system consists of several stages of pulse amplification culminating in 160 kV pulses having 30 ns risetime. The trigger system is described and test data provided.
Date: May 30, 1980
Creator: Cook, E. G.; Lauer, E. J.; Reginato, L. L.; Rogers, D. & Schmidt, J. A.
System: The UNT Digital Library
Overview of the ETA/ATA pulse power (open access)

Overview of the ETA/ATA pulse power

A pulsed electron accelerator has been constructed and is now in operation at the Lawrence Livermore Laboratory. This Experimental Test Accelerator (ETA) a 5 MeV, 10 kA, 50 ns FWHM, five pulse burst at 1 kHz, was designed to be the front end or injector for the Advanced Test Accelerator (ATA). The ATA is presently under construction and will have the following parameters: beam energy - 50 MeV, beam current - 10 kA, pulse length - 70 ns, repetition rate in a ten pulse burst - 1 kHz. The parameters which make the pulse power components unique for these machines are the high repetition rate in a burst and a high degree of regulation in the system to insure pulse to pulse repeatability. Because of the larger number of components requird for ATA, a much higher degree of reliability will be required. Improvements and modifications continue to be made on the ETA, which is serving as a base of development for all ATA pulse power components. Furthermore, all ATA pulse power components will be tested at length in a test stand before beginning mass production to insure proper design to meet voltage, current, rep-rate and life requirements.
Date: May 30, 1980
Creator: Reginato, L. L. & Hester, R. E.
System: The UNT Digital Library
Acceleration of polarized protons at the AGS (open access)

Acceleration of polarized protons at the AGS

Spin physics in the past has provided an acid test of many models and theories and over the last decade has revealed new and unexpected phenomena to confront present day theories. This work received great impetus from the experiments at the ZGS, where for the first time multi-GeV polarized beams became available. This, in conjunction with polarized targets, allowed the complete specification of the initial quantum states in high energy proton-proton interactions and led to many startling new results. Although spin effects were important at the previously measured lower energies, practically all theorists felt that spin effects would become negligible at higher energies. Instead, the ZGS results showed in many cases even larger effects than those observed at lower energies. By the time the ZGS was shut down in 1979, high energy polarized proton projects were planned for KEK in Japan, SATURNE in France, and the AGS at Brookhaven. At present, serious thought is being given to high energy polarized proton beams at Fermilab, CERN, and indeed in planning for the Superconducting Super Collider. Today, I would like to describe the facility at Brookhaven and give you the present status of the project. We have been in the commissioning phase …
Date: May 30, 1984
Creator: Ratner, L .G.
System: The UNT Digital Library
Hadron physics (open access)

Hadron physics

Is all hadronic physics ultimately describable by QCD. Certainly, many disparate phenomena can be understood within the QCD framework. Also certainly, there are important questions which are open, both theoretically (little guidance, as yet) and experimentally, regarding confinement. Are there dibaryons, baryonium, glueballs. In addition, there are experimental results which at present do not have an explanation. This talk, after a short section on QCD successes and difficulties, will emphasize two experimental topics which have recent results - glueball spectroscopy and exclusive reactions at large momentum transfer. Both are experimentally accessible in the AGS/LAMPF II/AGS II/TRIUMF II/SIN II energy domain.
Date: May 30, 1984
Creator: Bunce, G.
System: The UNT Digital Library
Workshop on compact storage ring technology: applications to lithography (open access)

Workshop on compact storage ring technology: applications to lithography

Project planning in the area of x-ray lithography is discussed. Three technologies that are emphasized are the light source, the lithographic technology, and masking technology. The needs of the semiconductor industry in the lithography area during the next decade are discussed, particularly as regards large scale production of high density dynamic random access memory devices. Storage ring parameters and an overall exposure tool for x-ray lithography are addressed. Competition in this area of technology from Germany and Japan is discussed briefly. The design of a storage ring is considered, including lattice design, magnets, and beam injection systems. (LEW)
Date: May 30, 1986
Creator: unknown
System: The UNT Digital Library
The Hispanic Heritage of Ranching in South Texas (open access)

The Hispanic Heritage of Ranching in South Texas

Paper discussing the evolution of south Texas ranching culture through the influence of Spanish, Mexican, and Anglo culture over different time periods.
Date: May 30, 1992
Creator: Graham, Joe Stanley, 1940-1999
System: The Portal to Texas History
Standard method for economic analyses of inertial confinement fusion power plants (open access)

Standard method for economic analyses of inertial confinement fusion power plants

A standard method for calculating the total capital cost and the cost of electricity for a typical inertial confinement fusion electric power plant has been developed. A standard code of accounts at the two-digit level is given for the factors making up the total capital cost of the power plant. Equations are given for calculating the indirect capital costs, the project contingency, and the time-related costs. Expressions for calculating the fixed charge rate, which is necessary to determine the cost of electricity, are also described. Default parameters are given to define a reference case for comparative economic analyses.
Date: May 30, 1986
Creator: Meier, W. R.
System: The UNT Digital Library
Off-nadir optical remote sensing from satellites for vegetation identification (open access)

Off-nadir optical remote sensing from satellites for vegetation identification

Today's satellite remote sensing systems rely heavily on spectral signatures for scene identification from nadir observations. We propose to use angular signatures as complementary scene identifiers when off-nadir sensing is possible. Specifically, the hot spot (Heiligenschein) of plant canopies is recognized as an atmosphere-invariant angular reflectance signature that carries information about the plant stand architecture which may be useful for instant crop identification from off-nadir satellite measurements.
Date: May 30, 1986
Creator: Gerstl, S.A.W.
System: The UNT Digital Library
Production and survival of /sup 99/Tc in He-shell recurrent thermal pulses (open access)

Production and survival of /sup 99/Tc in He-shell recurrent thermal pulses

After a brief introduction to the present state of art of nuclear beta-decay studies in astrophysics, we report our recent work on the long-standing /sup 99/Tc problem. Having combined a detailed study of the recurrent He-shell thermal-pulse, third dredge-up episodes in a 2.25 M/sub solar/ star and an s-process network calculation, we show that a substantial amount of /sup 99/Tc can be produced by the s-process and can survive to be dredged up to the stellar surface. We stress that the factual observation of /sup 99/Tc at the surface of certain stars does not necessarily preclude the /sup 22/Ne(..cap alpha..,n)/sup 25/Mg reaction from remaining as the neutron source for the s-process. The calculated surface abundances of /sup 99/Tc and elements with neighboring atomic numbers are compared with observations. 43 refs., 5 figs.
Date: May 30, 1985
Creator: Takahashi, K.; Mathews, G. J.; Ward, R. A. & Becker, S. A.
System: The UNT Digital Library