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Preparation of a strong, high prepressing intensity, and multifunction soybean protein adhesive by using hyperbranched functional polymer (open access)

Preparation of a strong, high prepressing intensity, and multifunction soybean protein adhesive by using hyperbranched functional polymer

Article states that the preparation of a soybean protein adhesive with good prepressing intensity, mildew proof, flame retardant, and high bond strength are conducive to the wide application of a soybean protein adhesive, which is important but challenging for the wood-based panel industry. In this study, two hyperbranched functional polymers were designed.
Date: January 9, 2023
Creator: Liu, Zheng; Liu, Tao; Zhang, Jieyu; Li, Yue; Luo, Jing; Li, Jianzhang et al.
System: The UNT Digital Library
Exhibiting Regional LGBTQ History in Dallas, Texas (open access)

Exhibiting Regional LGBTQ History in Dallas, Texas

Article on the efforts of the University of North Texas Special Collections to create exhibits featuring LGBTQ history in Dallas, Texas. From 2017 to 2019 archivists and librarians at the University of North Texas Special Collections have worked with community members and city officials to create exhibits featuring archival materials from the LGBTQ Archive. There have been several obstacles to presenting accurate historical interpretation of Dallas LGBTQ community history, including lack of sufficient archival documentation, and differences between archival sources and community members’ personal experiences. Grappling with these challenges has allowed UNT Special Collections archivists and librarians to engage community members in a personal, meaningful discussion, and ultimately have led to both successful exhibits as well as strengthened relationships to LGBTQ community members.
Date: January 9, 2021
Creator: Parker, Jaimi & Gieringer, Morgan Davis
System: The UNT Digital Library
Pyrolysis molecule of Torreya grandis bark for potential biomedicine (open access)

Pyrolysis molecule of Torreya grandis bark for potential biomedicine

Article describes study where a powder of torreya grandis bark was prepared and analyzed qualitatively and quantitativelyiIn order to explore a new way to utilize said bark.
Date: January 9, 2019
Creator: Chen, Huiling; Yue, Xiaochen; Yang, Jun; Lv, Chunxia; Dong, Shuaiwei; Luo, Xuefeng et al.
System: The UNT Digital Library
Experimental and theoretical evaluation of density sensitive N VII, Ar XIV and Fe XXII line ratios (open access)

Experimental and theoretical evaluation of density sensitive N VII, Ar XIV and Fe XXII line ratios

The line ratios of the 2p-3d transitions in the B-like spectra Ar XIV and Fe XXII have been measured using the electron beam ion traps at Livermore. Radiative-collisional model calculations show these line ratios to be sensitive to the electron density in the ranges ne = 10{sup 10} to 10{sup 12} cm{sup -3} and ne = 10{sup 13} to 10{sup 15} cm{sup -3}, respectively. In our experiment, the electron beam density of about 10{sup 11} cm{sup -3} was varied by about a factor of 5. Our data show a density effect for the line doublet in Ar XIV, and good agreement with theory is found. The relative intensity of the Fe XXII doublet shows good agreement with our predicted low density limit. The N VI K-shell spectrum was used to infer the actual electron density in the overlap region of ion cloud and electron beam, and systematic measurements and calculations of this spectrum are presented as well. The Ar XIV and Fe XXII spectra promise to be reliable density diagnostics for stellar coronae, complementing the K-shell diagnostics of helium-like ions.
Date: January 9, 2004
Creator: Chen, H; Beiersdorfer, P; Heeter, L A; Liedahl, D A; Naranjo-Rivera, K L; Trabert, E et al.
System: The UNT Digital Library
Predicting the rate by which suspended solids plug geothermal injection wells (open access)

Predicting the rate by which suspended solids plug geothermal injection wells

Standard membrane filtration tests were used to evaluate injection at the Salton Sea Geothermal Field, Southern California. Results indicate that direct injection into reservoir zones with primary porosity is not feasible unless 1 ..mu..m or larger particulates formed during or after the energy conversion process are removed. (JGB)
Date: January 9, 1978
Creator: Owens, L. B.; Kasameyer, P. W.; Netherton, R. & Thorson, L.
System: The UNT Digital Library
Multiscale modeling of dislocation processes in BCC tantalum: bridging atomistic and mesoscale simulations (open access)

Multiscale modeling of dislocation processes in BCC tantalum: bridging atomistic and mesoscale simulations

Plastic deformation in bcc metals at low temperatures and high-strain rates is controlled by the motion of a/2<111> screw dislocations, and understanding the fundamental atomistic processes of this motion is essential to develop predictive multiscale models of crystal plasticity. The multiscale modeling approach presented here for bcc Ta is based on information passing, where results of simulations at the atomic scale are used in simulations of plastic deformation at mesoscopic length scales via dislocation dynamics (DD). The relevant core properties of a/2<111> screw dislocations in Ta have been obtained using quantum-based interatomic potentials derived from model generalized pseudopotential theory and an ab-initio data base together with an accurate Green's-function simulation method that implements flexible boundary conditions. In particular, the stress-dependent activation enthalpy for the lowest-energy kink-pair mechanism has been calculated and fitted to a revealing analytic form. This is the critical quantity determining dislocation mobility in the DD simulations, and the present activation enthalpy is found to be in good agreement with the previous empirical form used to explain the temperature dependence of the yield stress.
Date: January 9, 2001
Creator: Yang, L H; Tang, M & Moriarty, J A
System: The UNT Digital Library
Functionalized Silicon Membranes for Selective Bio-Organisms Capture (open access)

Functionalized Silicon Membranes for Selective Bio-Organisms Capture

Membranes with various pore size, length, morphology and density have been synthesized out of diverse materials for size exclusion-based separation. An example of application is the sterilization of intravenous lines by exclusion of bacteria and viruses using Polyvinylidene Fluoride membranes with 0.1 {micro}m diameter pores. The need for chemically specific filtration has recently been addressed, but for small molecules only. An important problem remaining to be solved is the selective capture of large bio-organisms for decontamination or analysis of air and liquids such as drinking water and body fluids. To achieve this goal, materials with controlled pore diameter, length and surface chemistry are required. In this letter, we present the first functionalized silicon membranes and demonstrate their ability to selectively capture simulated bio-organisms. These extremely versatile and rigid devices open the door on a new class of materials able to recognize the external fingerprints of bio-organisms such as size and outer membrane proteins for specific capture and detection applications.
Date: January 9, 2003
Creator: Letant, S E; Hart, B R; van Buuren, A W & Terminello, L J
System: The UNT Digital Library
Comparison of imaging spectrometers (open access)

Comparison of imaging spectrometers

Realistic signal to noise performance estimates for the various types of instruments being considered for NGST are compared, based on the point source detection values quoted in the available ISIM final reports. The corresponding sensitivity of the various types of spectrometers operating in a full field imaging mode, for both emission line objects and broad spectral distribution objects, is computed and displayed. For the purpose of seeing the earliest galaxies, or the faintest possible emission line sources, the imaging Fourier transform spectrometer emerges superior to all others, by orders of magnitude in speed.
Date: January 9, 2000
Creator: Bennett, C
System: The UNT Digital Library
Prospects for Investigating Unusual Nuclear Reaction Environments Using the National Ignition Facility (open access)

Prospects for Investigating Unusual Nuclear Reaction Environments Using the National Ignition Facility

The standard capsule design and other laser plasma targets at the National Ignition Facility offer the possibility of generating and studying thermal rates for significant astrophysical fusion reactions such as {sup 3}He({sup 3}He,2p){alpha}, {sup 7}Be(p,{gamma}){sup 8}B, and {sup 15}N(p,{alpha}){sup 12}C. At present the ''S'' factors for these reactions are determined either by extrapolation from higher energy scattering data, or by underground laboratory, low event rate experiments such as at LUNA on un-ionized atoms with concomitantly large screening corrections. The ability to directly generate astrophysical fusion reactions in thermonuclear plasmas will be complemented by new, ab initio, ''no frozen core'' detailed shell model predictions for such light ion reactions. In addition, the expected fluence of neutrons from the main D + T {yields} {alpha} + n burn reaction, is high enough to drive 10-20% of seeded spectator nuclei into excited states via (n,n') reactions. Furthermore, the {approx}2% ''minority'' D + D {yields} {sup 3}He + n and n + D {yields} n' + D' scattering can drive reactions pertinent to the r, s, and p process nucleosynthesis of heavy elements, including branches that pass through excited states with t > 10 ps, that can be studied using particle spectroscopy and radiochemistry. …
Date: January 9, 2004
Creator: Libby, S. B.; Tabak, M.; Hoffman, R. D.; Stoyer, M. A.; Haan, S. W.; Hatchett, S. P. et al.
System: The UNT Digital Library
BioZoom: Exploiting Source-Capability Information for Integrated Access to Multiple Bioinformatics Data Sources (open access)

BioZoom: Exploiting Source-Capability Information for Integrated Access to Multiple Bioinformatics Data Sources

Modern Bioinformatics data sources are widely used by molecular biologists for homology searching and new drug discovery. User-friendly and yet responsive access is one of the most desirable properties for integrated access to the rapidly growing, heterogeneous, and distributed collection of data sources. The increasing volume and diversity of digital information related to bioinformatics (such as genomes, protein sequences, protein structures, etc.) have led to a growing problem that conventional data management systems do not have, namely finding which information sources out of many candidate choices are the most relevant and most accessible to answer a given user query. We refer to this problem as the query routing problem. In this paper we introduce the notation and issues of query routing, and present a practical solution for designing a scalable query routing system based on multi-level progressive pruning strategies. The key idea is to create and maintain source-capability profiles independently, and to provide algorithms that can dynamically discover relevant information sources for a given query through the smart use of source profiles. Compared to the keyword-based indexing techniques adopted in most of the search engines and software, our approach offers fine-granularity of interest matching, thus it is more powerful and …
Date: January 9, 2003
Creator: Liu, Ling; Buttler, David; Critchlow, Terence J.; Han, Wei; Paques, Henrique; Pu, Calton et al.
System: The UNT Digital Library
Nanopatterned Graphene Field Effect Transistor Fabricated Using Block Co-polymer Lithography (open access)

Nanopatterned Graphene Field Effect Transistor Fabricated Using Block Co-polymer Lithography

This article demonstrates a successful fabrication of Nanopatterened Graphene (NPG) using a PS-b-P4VP polymer.
Date: January 9, 2014
Creator: Choi, Duyoung; Kuru, Cihan; Choi, Chulmin; Noh, Kunbae; Hong, Soon-Kook; Das, Santanu et al.
System: The UNT Digital Library

Do Neighborhoods Matter Differently for Movers and Non-Movers?: Analysis of Weight Gain in the Longitudinal Dallas Heart Study

This article uses data from the Dallas Heart Study to evaluate the relationship between changes in neighborhood condition and weight change for both movers and non-movers over an approximate seven-year follow-up period.
Date: May 10, 2016
Creator: Leonard, Tammy; Ayers, Colby; Das, Sandeep R.; Neeland, Ian J. & Powell-Wiley, Tiffany M.
System: The UNT Digital Library
Spectroscopic study of tetradecyltrimethylammonium bromide Pt-C14TAB nanoparticles: Structure and Stability (open access)

Spectroscopic study of tetradecyltrimethylammonium bromide Pt-C14TAB nanoparticles: Structure and Stability

The vibrational spectra of platinum nanoparticles (12 nm) capped with tetradecyltrimethylammonium bromide, C{sub 14}TAB, were investigated by Fourier transform infrared (FTIR) spectroscopy. We have shown that the thermal decay of Pt-C{sub 14}TAB nanoparticles in N{sub 2}, H{sub 2} and O{sub 2} atmospheres leads to the release of hydrocarbon chain of surfactant and the formation of strongly bonded layer of ammonium cations on the platinum surface. The platinum atoms accessible to CO chemisorptions were not reducible by hydrogen in the temperature ranging from 30 C to 200 C. A FTIR spectrum of C{sub 14}TAB adsorbed on Pt nanoparticles dramatically perturbed as compared with pure C{sub 14}TAB. New intense and broad bands centered at 1450 cm{sup -1} and 760 cm{sup -1} are making their appearance in Pt-C{sub 14}TAB. It may be speculated, that new bands are result of coupling between conducting electrons of Pt and molecular vibrations of adsorbed C{sub 14}TAB and as a consequence specific vibrational modes of ammonium cation transformed into electron-vibrational modes.
Date: January 9, 2009
Creator: Borodko, Y.; Jones, L.; Frei, H. & Somorjai, G.
System: The UNT Digital Library
Study on Auto-DR and Pre-Cooling of Commercial Buildings with Thermal Mass in California (open access)

Study on Auto-DR and Pre-Cooling of Commercial Buildings with Thermal Mass in California

This paper discusses how to optimize pre-cooling strategies for buildings in a hot California climate zone with the Demand Response Quick Assessment Tool (DRQAT), a building energy simulation tool. This paper outlines the procedure used to develop and calibrate DRQAT simulation models, and applies this procedure to eleven field test buildings. The results of a comparison between the measured demand savings during the peak period and the savings predicted by the simulation model indicate that the predicted demand shed match well with measured data for the corresponding auto-demand response (Auto-DR) days. The study shows that the accuracy of the simulation models is greatly improved after calibrating the initial models with measured data. These improved models can be used to predict load reductions for automated demand response events. The simulation results were compared with field test data to confirm the actual effect of demand response strategies. Results indicate that the optimal demand response strategies worked well for most of the buildings tested in this hot climate zone.
Date: January 9, 2010
Creator: Yin, Rongxin; Xu, Peng; Piette, Mary Ann & Kiliccote, Sila
System: The UNT Digital Library
Recent Development of Two-Dimensional Transition Metal Dichalcogenides and Their Applications (open access)

Recent Development of Two-Dimensional Transition Metal Dichalcogenides and Their Applications

This article reviews the recent progress in 2D materials beyond graphene and includes mainly transition metal dichalcogenides.
Date: January 9, 2017
Creator: Choi, Wonbong; Choudhary, Nitin; Han, Gang Hee; Park, Juhong; Akinwande, Deji & Lee, Young Hee
System: The UNT Digital Library
Coherent rho 0 photoproduction in bulk matter at high energies (open access)

Coherent rho 0 photoproduction in bulk matter at high energies

The momentum transfer {Delta}k required for a photon to scatter from a target and emerge as a {rho}{sup 0} decreases as the photon energy k rises. For k > 3 x 10{sup 14} eV, {Delta}k is small enough that the interaction cannot be localized to a single nucleus. At still higher energies, photons may coherently scatter elastically from bulk matter and emerge as a {rho}{sup 0}, in a manner akin to kaon regeneration. Constructive interference from the different nuclei coherently raises the cross section and the interaction probability rises linearly with energy. At energies above 10{sup 23} eV, coherent conversion is the dominant process; photons interact predominantly as {rho}{sup 0}. We compute the coherent scattering probabilities in slabs of lead, water and rock, and discuss the implications of the increased hadronic interaction probabilities for photons on ultra-high energy shower development.
Date: January 9, 2009
Creator: Couderc, Elsa & Klein, Spencer
System: The UNT Digital Library
Understanding the mechanism of base development of hydrogen silsesquioxane (open access)

Understanding the mechanism of base development of hydrogen silsesquioxane

There have been numerous studies of electron beam exposed hydrogen silsesquioxane (HSQ) development conditions in order to improve the developer contrast. For TMAH based development, improvements were made by going to higher TMAH normalities and heating the developer. Yang and Berggren showed development of electron beam exposed (HSQ) by NaOH with added Na salts (various anions) significantly improves the contrast. Here, we study the contrast and etching rates of 100 keV exposed HSQ in NaOH in the presence of LiCl, NaCl, and KCl salts and use this as a segway to understand the mechanisms governing contrast during development HSQ development. The basic mechanism of development of HSQ can be understood by comparing to etching of quartz in basic solutions. Hydroxide ions act as nucleophiles which attack silicon. When a silicon-oxygen bond of the Si-O-Si matrix is broken, Si-O{sup -} and Si-OH are formed which can reversibly react to form the original structure. When a Si-H bond is broken via reaction with hydroxide, Si-O{sup -} and H{sub 2} gas are formed. Salts can change the etching rates as a function of dose in a non-linear fashion to increase etch contrast. Figs. 1, 2, and 3 show contrast curves for HSQ developed …
Date: January 9, 2009
Creator: Kim, Jihoon; Chao, Weilun; Liang, Xiaogan; Griedel, Brian D. & Olynick, Deirdre L
System: The UNT Digital Library
Epitaxial growth and characterization of CaVO3 thin films (open access)

Epitaxial growth and characterization of CaVO3 thin films

Epitaxial thin films of CaVO{sub 3} were synthesized on SrTiO{sub 3}, LaAlO{sub 3} and (La{sub 0.27}Sr{sub 0.73})(Al{sub 0.65}Ta{sub 0.35})O{sub 3} substrates by pulsed laser deposition. All CaVO{sub 3} films, independent of epitaxial strain, exhibit metallic and Pauli paramagnetic behavior as CaVO{sub 3} single crystals. X-ray absorption measurements confirmed the 4+ valence state for Vanadium ions. With prolonged air exposure, an increasing amount of V{sup 3+} is detected and is attributed to oxygen loss in the near surface region of the films.
Date: January 9, 2009
Creator: Liberati, Marco; Chopdekar, R.V.; Mehta, V.; Arenholz, E. & Suzuki, Y.
System: The UNT Digital Library
Double patterning HSQ processes of zone plates for 10 nm diffraction limitedperformance (open access)

Double patterning HSQ processes of zone plates for 10 nm diffraction limitedperformance

In e-beam lithography, fabrication of sub-20 nm dense structures is challenging. While there is a constant effort to develop higher resolution resist processes, the progress of increasing pattern density is slow. For zone plates, consisting of dense lines and spaces, the outermost zone width has been limited to slightly less than 20 nm due to effects such as low aerial image contrast, forward scattering, intrinsic resist resolution, and development issues. To circumvent these effects, we have successfully developed a new double patterning HSQ process, and as a result, we have fabricated zone plates of 10 and 12 nm using the process. We previously developed a double patterning process in which a dense zone plate pattern is sub-divided into two semi-isolated, complementary zone set patterns. These patterns are fabricated separately and then overlaid with high accuracy to yield the desired pattern. The key to success with this process is the accuracy of the overlay. For diffraction-limited zone plates, accuracy better than one-third of the smallest zone width is needed. In our previous work, the zone set patterns were formed using PMMA and gold electroplating, which were overlaid and aligned to the zero-level mark layer with sub-pixel accuracy using our internally developed …
Date: January 9, 2009
Creator: Chao, Weilun; Kim, Jihoon; Anderson, Erik H.; Fischer, Peter; Rekawa, Senajith & Attwood, David T.
System: The UNT Digital Library
On a solution to the problem of the poor cyclic fatigue resistance of bulk metallic glasses (open access)

On a solution to the problem of the poor cyclic fatigue resistance of bulk metallic glasses

The recent development of metallic glass-matrix composites represents a particular milestone in engineering materials for structural applications owing to their remarkable combinations of strength and toughness. However, metallic glasses are highly susceptible to cyclic fatigue damage and previous attempts to solve this problem have been largely disappointing. Here we propose and demonstrate a microstructural design strategy to overcome this limitation by matching the microstructural length scales (of the second phase) to mechanical crack-length scales. Specifically, semi-solid processing is used to optimize the volume fraction, morphology, and size of second phase dendrites to confine any initial deformation (shear banding) to the glassy regions separating dendrite arms having length scales of {approx} 2 {micro}m, i.e., to less than the critical crack size for failure. Confinement of the damage to such interdendritic regions results in enhancement of fatigue lifetimes and increases the fatigue limit by an order of magnitude making these 'designed' composites as resistant to fatigue damage as high-strength steels and aluminum alloys. These design strategies can be universally applied to any other metallic glass systems.
Date: January 9, 2009
Creator: Launey, Maximilien E.; Hofmann, Douglas C.; Johnson, William L. & Ritchie, Robert O.
System: The UNT Digital Library
M-theory and E10: Billiards, Branes, and Imaginary Roots (open access)

M-theory and E10: Billiards, Branes, and Imaginary Roots

Eleven dimensional supergravity compactified on $T^10$ admits classical solutions describing what is known as billiard cosmology - a dynamics expressible as an abstract (billiard) ball moving in the 10-dimensional root space of the infinite dimensional Lie algebra E10, occasionally bouncing off walls in that space. Unlike finite dimensional Lie algebras, E10 has negative and zero norm roots, in addition to the positive norm roots. The walls above are related to physical fluxes that, in turn, are related to positive norm roots (called real roots) of E10. We propose that zero and negative norm roots, called imaginary roots, are related to physical branes. Adding 'matter' to the billiard cosmology corresponds to adding potential terms associated to imaginary roots. The, as yet, mysterious relation between E10 and M-theory on $T^10$ can now be expanded as follows: real roots correspond to fluxes or instantons, and imaginary roots correspond to particles and branes (in the cases we checked). Interactions between fluxes and branes and between branes and branes are classified according to the inner product of the corresponding roots (again in the cases we checked). We conclude with a discussion of an effective Hamiltonian description that captures some features of M-theory on $T^10.$
Date: January 9, 2004
Creator: Brown, Jeffrey; Ganor, Ori J. & Helfgott, Craig
System: The UNT Digital Library
Complexity matching in neural networks (open access)

Complexity matching in neural networks

This article adopts the complexity matching principle that the maximal efficiency of communication between two complex networks is realized when both of them are at criticality, and uses this principle to establish the value of the neuronal interaction strength at which criticality occurs.
Date: January 9, 2015
Creator: Mafahim, Javad Usefie; Lambert, David; Zare, Marzieh & Grigolini, Paolo
System: The UNT Digital Library
Theory and Fluid Simulations of Boundary Plasma Fluctuations (open access)

Theory and Fluid Simulations of Boundary Plasma Fluctuations

Theoretical and computational investigations are presented of boundary plasma microturbulence that take into account important effects of the geometry of diverted tokamaks--in particular, the effect of x-point magnetic shear and the termination of field lines on divertor plates. We first generalize our previous 'heuristic boundary condition' which describes, in a lumped model, the closure of currents in the vicinity of the x-point region to encompass three current-closure mechanisms. We then use this boundary condition to derive the dispersion relation for low-beta flute-like modes in the divertor-leg region under the combined drives of curvature, sheath impedance, and divertor tilt effects. The results indicate the possibility of strongly growing instabilities, driven by sheath boundary conditions, and localized in either the private or common flux region of the divertor leg depending on the radial tilt of divertor plates. We re-visit the issue of x-point effects on blobs, examining the transition from blobs terminated by x-point shear to blobs that extend over both the main SOL and divertor legs. We find that, for a main-SOL blob, this transition occurs without a free-acceleration period as previously thought, with x-point termination conditions applying until the blob has expanded to reach the divertor plate. We also derive …
Date: January 9, 2007
Creator: Cohen, R. H.; LaBombard, B.; LoDestro, L. L.; Rognlien, T. D.; Ryutov, D. D.; Terry, J. L. et al.
System: The UNT Digital Library
Light-Front Holography and QCD Hadronization at the Amplitude Level (open access)

Light-Front Holography and QCD Hadronization at the Amplitude Level

Light-front holography allows hadronic amplitudes in the AdS/QCD fifth dimension to be mapped to frame-independent light-front wavefunctions of hadrons in physical space-time, thus providing a relativistic description of hadrons at the amplitude level. The AdS coordinate z is identified with an invariant light-front coordinate {zeta} which separates the dynamics of quark and gluon binding from the kinematics of constituent spin and internal orbital angular momentum. The result is a single-variable light-front Schroedinger equation for QCD which determines the eigenspectrum and the light-front wavefunctions of hadrons for general spin and orbital angular momentum. A new method for computing the hadronization of quark and gluon jets at the amplitude level using AdS/QCD light-front wavefunctions is outlined.
Date: January 9, 2009
Creator: Brodsky, Stanley J. & de Teramond, Guy F.
System: The UNT Digital Library