Resource Type

Changes in Deep Soil Water Content in the Process of Large-Scale Apple Tree Planting on the Loess Tableland of China (open access)

Changes in Deep Soil Water Content in the Process of Large-Scale Apple Tree Planting on the Loess Tableland of China

This article evaluates the effects of orchard development on deep soil water content (SWC) by using a meta-analysis of 162 sampling sites on the loess tableland from 44 peer-reviewed publications. The results showed that the deep SWC in orchards depended on stand age, planting density and annual precipitation.
Date: January 23, 2021
Creator: Wang, Yaping; Yan, Weiming; Han, Xiaoyang; Pan, Feifei; Cheng, Liping & Liu, Wenzhao
System: The UNT Digital Library
Automatic Extraction of Grasses and Individual Trees in Urban Areas Based on Airborne Hyperspectral and LiDAR Data (open access)

Automatic Extraction of Grasses and Individual Trees in Urban Areas Based on Airborne Hyperspectral and LiDAR Data

This article proposes a three-dimensional (3D) vegetation extraction workflow to extract urban grasses and trees at individual tree level in urban areas using airborne LiDAR and hyperspectral data. Results suggest that two- and three-dimensional urban vegetation extraction could play a significant role in spatial layout optimization and scientific management of urban vegetation.
Date: August 23, 2020
Creator: Man, Qixia; Dong, Pinliang; Yang, Xinming; Wu, Quanyuan & Han, Rongqing
System: The UNT Digital Library
Matt Swinney grew Austin's fashion scene one Fashion X at a time (open access)

Matt Swinney grew Austin's fashion scene one Fashion X at a time

Article about Matt Swinney, founder of Fashion X, and the 10 year anniversary of Austin Fashion Week.
Date: September 23, 2018
Creator: Villalpando, Nicole
System: The UNT Digital Library
Random Vibrations: Assessment of the State of the Art (open access)

Random Vibrations: Assessment of the State of the Art

Random vibration is the phenomenon wherein random excitation applied to a mechanical system induces random response. We summarize the state of the art in random vibration analysis and testing, commenting on history, linear and nonlinear analysis, the analysis of large-scale systems, and probabilistic structural testing.
Date: February 23, 1999
Creator: Paez, Thomas L.
System: The UNT Digital Library
Unique Challenges Accompany Thick-Shell CdSe/nCdS (n > 10) Nanocrystal Synthesis (open access)

Unique Challenges Accompany Thick-Shell CdSe/nCdS (n > 10) Nanocrystal Synthesis

Thick-shell CdSe/nCdS (n {ge} 10) nanocrystals were recently reported that show remarkably suppressed fluorescence intermittency or 'blinking' at the single-particle level as well as slow rates of Auger decay. Unfortunately, whereas CdSe/nCdS nanocrystal synthesis is well-developed up to n {le} 6 CdS monolayers (MLs), reproducible syntheses for n {ge} 10 MLs are less understood. Known procedures sometimes result in homogeneous CdS nucleation instead of heterogeneous, epitaxial CdS nucleation on CdSe, leading to broad and multimodal particle size distributions. Critically, obtained core/shell sizes are often below those desired. This article describes synthetic conditions specific to thick-shell growth (n {ge} 10 and n {ge} 20 MLs) on both small (sub2 nm) and large (>4.5 nm) CdSe cores. We find added secondary amine and low concentration of CdSe cores and molecular precursors give desired core/shell sizes. Amine-induced, partial etching of CdSe cores results in apparent shell-thicknesses slightly beyond those desired, especially for very-thick shells (n {ge} 20 MLs). Thermal ripening and fast precursor injection lead to undesired homogeneous CdS nucleation and incomplete shell growth. Core/shells derived from small CdSe (1.9 nm) have longer PL lifetimes and more pronounced blinking at single-particle level compared with those derived from large CdSe (4.7 nm). We expect …
Date: December 23, 2011
Creator: Guo, Yijun; Marchuk, Kyle; Sampat, Siddharth; Abraham, Rachel; Fang, Ning; Malko, Anton V. et al.
System: The UNT Digital Library
pi. /sup -/p. -->. K/sub s//sup 0/K/sub s//sup 0/n at 22 Gev/c and a Systematic Study of the 2/sup + +/ and 0/sup + +/ Meson Spectrum (open access)

pi. /sup -/p. -->. K/sub s//sup 0/K/sub s//sup 0/n at 22 Gev/c and a Systematic Study of the 2/sup + +/ and 0/sup + +/ Meson Spectrum

A coupled channel analysis has been carried out using amplitudes of the K/sub s//sup 0/K/sub s//sup 0/ system produced in the reaction ..pi../sup -/p ..-->.. K/sub s//sup 0/K/sub s//sup 0/n at 22 Gev/c, which contained about 40,000 events in the low-t region (absolute value of t-tmin < 0.1 Gev/sup 2/). The I/sup G/ = 0/sup +/, J/sup PC/ = 0/sup + +/, 2/sup + +/, 4/sup + +/ amplitudes from this analysis is considered, together with available data from other experiments in channels with the same quantum numbers in order to determine which 0/sup + +/ and 2/sup + +/ isoscalar mesons have significant pseudoscalar-pseudoscalar couplings. It is found that we need one pole for the 4/sup + +/ amplitudes while the 2/sup + +/ needs five poles and the 0/sup + +/ needs 7 poles.
Date: June 23, 1987
Creator: Longacre, R. S.; Etkin, A.; Foley, K. J.; Love, W. A.; Morris, T. W.; Platner, E. D. et al.
System: The UNT Digital Library
Identification of Novel Antimicrobial Resistance Genes Using Machine Learning, Homology Modeling, and Molecular Docking (open access)

Identification of Novel Antimicrobial Resistance Genes Using Machine Learning, Homology Modeling, and Molecular Docking

Article claims antimicrobial resistance (AMR) threatens the healthcare system worldwide with the rise of emerging drug resistant infectious agents. To infer novel resistance genes, we used complete gene sets of several bacterial strains known to be susceptible or resistant to specific drugs and associated phenotypic information within a machine learning framework that enabled prioritizing genes potentially involved in resistance.
Date: October 23, 2022
Creator: Sunuwar, Janak & Azad, Rajeev K.
System: The UNT Digital Library
Object-Oriented Canopy Gap Extraction from UAV Images Based on Edge Enhancement (open access)

Object-Oriented Canopy Gap Extraction from UAV Images Based on Edge Enhancement

Article describes the efficient and accurate identification of canopy gaps is the basis of forest ecosystem research, which is of great significance to further forest monitoring and management. One major limitation of the traditional methods of remote sensing to map canopy gaps is that they cannot finely extract the complex edges of canopy gaps in mountainous areas. The authors proposed an object-oriented classification method that integrates multi-source information.
Date: September 23, 2022
Creator: Xia, Jisheng; Wang, Yutong; Dong, Pinliang; He, Shijun; Zhao, Fei & Luan, Guize
System: The UNT Digital Library
Light-Controlled Cell–Cell Assembly Using Photocaged Oligonucleotides (open access)

Light-Controlled Cell–Cell Assembly Using Photocaged Oligonucleotides

Article asserts that while techniques that allow one to control the arrangement of cells and direct contact between different cell types have been developed that expand upon simple co-culture methods, specific control over heterojunctions that form between cells is not easily accomplished with current methods, such as 3D cell-printing. In this article, DNA-mediated cell interactions are combined with cell-compatible photolithographic approaches to control cell assembly.
Date: May 23, 2023
Creator: Mathis, Katelyn; Kohon, Agia Ibnat; Black, Stephen & Meckes, Brian
System: The UNT Digital Library
A 15-T Pulsed Solenoid for a High-Power Target Experiment (open access)

A 15-T Pulsed Solenoid for a High-Power Target Experiment

The MERIT experiment, which ran at CERN in 2007, is a proof-of-principle test for a target system that converts a 4-MW proton beam into a high-intensity muon beam for either a neutrino factory complex or a muon collider. The target system is based on a free mercury jet that intercepts an intense proton beam inside a 15-T solenoidal magnetic field. Here, we describe the design and performance of the 15-T, liquid-nitrogen-precooled, copper solenoid magnet.
Date: June 23, 2008
Creator: Kirk, H. G.; Efthymiopoulos, I.; Fabich, A.; Haug, F.; Pereira, H.; Titus, P. et al.
System: The UNT Digital Library
On the crystalline structure, stoichiometry and band gap of InN thin films (open access)

On the crystalline structure, stoichiometry and band gap of InN thin films

Detailed transmission electron microscopy (TEM), x-ray diffraction (XRD), and optical characterization of a variety of InN thin films grown by molecular beam epitaxy under both optimized and non-optimized conditions is reported. Optical characterization by absorption and photoluminescence confirms that the band gap of single crystalline and polycrystalline wurtzite InN is 0.70 {+-} 0.05 eV. Films grown under optimized conditions with a AlN nucleation layer and a GaN buffer layer are stoichiometric, single crystalline wurtzite structure with dislocation densities not exceeding mid-10{sup 10} cm{sup -2}. Non-optimal films can be poly-crystalline and display an XRD diffraction feature at 2{theta} {approx} 33{sup o}; this feature has been attributed by others to the presence of metallic In clusters. Careful indexing of wide angle XRD scans and selected area diffraction patterns shows that this peak is in fact due to the presence of polycrystalline InN grains; no evidence of metallic In clusters was found in any of the studied samples.
Date: September 23, 2004
Creator: Yu, K. M.; Liliental-Weber, Z.; Walukiewicz, W.; Li, S. X.; Jones, R. E.; Shan, W. et al.
System: The UNT Digital Library
Aerosol-Assisted Self-Assembly of Mesostructured Spherical Nanoparticles (open access)

Aerosol-Assisted Self-Assembly of Mesostructured Spherical Nanoparticles

Nanostructured particles exhibiting well-defined pore sizes and pore connectivities (1-, 2-, or 3-dimensional) are of interest for catalysis, chromatography, controlled release, low dielectric constant fillers, and custom-designed pigments and optical hosts. During the last several years considerable progress has been made on controlling the macroscopic forms of mesoporous silicas prepared by surfactant and block copolymer liquid crystalline templating procedures. Typically interfacial phenomena are used to control the macroscopic form (particles, fibers, or films), while self-assembly of amphiphilic surfactants or polymers is used to control the mesostructure. To date, although a variety of spherical or nearly-spherical particles have been prepared, their extent of order is limited as is the range of attainable mesostructures. They report a rapid, aerosol process that results in solid, completely ordered spherical particles with stable hexagonal, cubic, or vesicular mesostructures. The process relies on evaporation-induced interfacial self-assembly (EISA) confined to a spherical aerosol droplet. The process is simple and generalizable to a variety of materials combinations. Additionally, it can be modified to provide the first aerosol route to the formation of ordered mesostructured films.
Date: March 23, 1999
Creator: Lu, Yunfeng; Fan, Hongyou; Stump, Aaron; Ward, Timothy, L.; Rieker, Thomas & Brinker, C. Jeffrey
System: The UNT Digital Library
Spin Effects in the Fragmentation of Transversely Polarized and Unpolarized Quarks. (open access)

Spin Effects in the Fragmentation of Transversely Polarized and Unpolarized Quarks.

We study the fragmentation of a transversely polarized quark into a non-collinear (k{perpendicular} {ne} 0) spinless hadron and the fragmentation of an unpolarized quark into a non collinear transversely polarized spin 1/2 baryon. These nonperturbative properties are described by spin and k{perpendicular} dependent fragmentation functions and are revealed in the observation of single spin asymmetries. Recent data on the production of pions in polarized semi-inclusive DIS and long known data on A polarization in unpolarized p-N processes are considered: these new fragmentation functions can describe the experimental results and the single spin effects in the quark fragmentation turn out to be surprisingly large.
Date: April 23, 2001
Creator: Anselmino, M.; Boer, D.; D'Alesio, U. & Murgia, F.
System: The UNT Digital Library
Catalog of ARM External Data. (open access)

Catalog of ARM External Data.

None
Date: March 23, 1998
Creator: Tichler, J. L.
System: The UNT Digital Library
Band anticrossing in dilute nitrides (open access)

Band anticrossing in dilute nitrides

Alloying III-V compounds with small amounts of nitrogen leads to dramatic reduction of the fundamental band-gap energy in the resulting dilute nitride alloys. The effect originates from an anti-crossing interaction between the extended conduction-band states and localized N states. The interaction splits the conduction band into two nonparabolic subbands. The downward shift of the lower conduction subband edge is responsible for the N-induced reduction of the fundamental band-gap energy. The changes in the conduction band structure result in significant increase in electron effective mass and decrease in the electron mobility, and lead to a large enhance of the maximum doping level in GaInNAs doped with group VI donors. In addition, a striking asymmetry in the electrical activation of group IV and group VI donors can be attributed to mutual passivation process through formation of the nearest neighbor group-IV donor nitrogen pairs.
Date: December 23, 2003
Creator: Shan, W.; Yu, K. M.; Walukiewicz, W.; Wu, J.; Ager, J. W., III & Haller, E. E.
System: The UNT Digital Library
Pulsed-Laser Deposited Amorphous Diamond and Related Materials: Synthesis, Characterization, and Field Emission Properties (open access)

Pulsed-Laser Deposited Amorphous Diamond and Related Materials: Synthesis, Characterization, and Field Emission Properties

Amorphous carbon films with variable sp{sup 3} content were produced by ArF (193nm) pulsed laser deposition. An in-situ ion probe was used to measure kinetic energy of C{sup +} ions. In contrast to measurements made as a function of laser fluence, ion probe measurements of kinetic energy are a convenient as well as more accurate and fundamental method for monitoring deposition conditions, with the advantage of being readily transferable for inter-laboratory comparisons. Electron energy loss spectroscopy (EELS) and spectroscopic ellipsometry measurements reveal that tetrahedral amorphous carbon (ta-C) films with the most diamond-like properties are obtained at the C ion kinetic energy of {approximately}90 eV. Film properties are uniform within a 12-15{degree} angle from the plume centerline. Tapping-mode atomic force microscope measurements show that films deposited at near-optimum kinetic energy are extremely smooth, with rms roughness of only {approximately} 1 {angstrom} over distances of several hundred nm. Field emission (FE) measurements show that ta-C does not appear to be a good electron emitter. After conditioning of ta-C films deposited on n-type Si a rather high turn-on voltage of {approximately}50 V/{micro}m was required to draw current of {approximately}1 nA to the probe. The emission was unstable and typically ceased after a few …
Date: January 23, 1999
Creator: Baylor, L. R.; Geohegan, D. B.; Jellison, G. E., Jr.; Lowndes, D. H.; Merkulov, V. I. & Puretzky, A. A.
System: The UNT Digital Library
Accident Management & Risk-Based Compliance With 40 CFR 68 for Chemical Process Facilities (open access)

Accident Management & Risk-Based Compliance With 40 CFR 68 for Chemical Process Facilities

A risk-based logic model is suggested as an appropriate basis for better predicting accident progression and ensuing source terms to the environment from process upset conditions in complex chemical process facilities. Under emergency conditions, decision-makers may use the Accident Progression Event Tree approach to identify the best countermeasure for minimizing deleterious consequences to receptor groups before the atmospheric release has initiated. It is concluded that the chemical process industry may use this methodology as a supplemental information provider to better comply with the Environmental Protection Agency`s proposed 40 CFR 68 Risk Management Program rule. An illustration using a benzene-nitric acid potential interaction demonstrates the value of the logic process. The identification of worst-case releases and planning for emergency response are improved through these methods, at minimum. It also provides a systematic basis for prioritizing facility modifications to correct vulnerabilities.
Date: August 23, 1995
Creator: O`Kula, K. R.; Taylor, R. P., Jr. & Ashbaugh, S. G.
System: The UNT Digital Library
Hyperemesis gravidarum and the risk of childhood cancer- A case-control study in Denmark (open access)

Hyperemesis gravidarum and the risk of childhood cancer- A case-control study in Denmark

Article describes how only a few studies have reported on the association between hyperemesis gravidarum and the risk of childhood cancer. The authors examined possible associations in this population-based study in Denmark.
Date: October 23, 2023
Creator: Orimoloye, Helen T.; Deng, Chuanjie; Hansen, Johnni; Olsen, Jorn; Saechao, Chai; Ritz, Beate et al.
System: The UNT Digital Library
Laser printed amorphous magnesium alloy: Microstructure, mechanical properties, and degradation behavior (open access)

Laser printed amorphous magnesium alloy: Microstructure, mechanical properties, and degradation behavior

Article describes how, amorphous magnesium alloy, especially Mg-Zn-Ca series, has been receiving continuous attention in biomedical field, because of its favorable corrosion resistance, suitable modulus and biocompatibility. In this work, laser powder bed fusing with unique characteristics of rapid solidification and layer-by-layer fashion was used to fabricate bulk Mg-Zn-Ca and Mg-Zn-Ca-Y amorphous parts.
Date: November 23, 2023
Creator: Chen, Cheng; Li, Shaoyu; Ling, Chenrong; Yang, Youwen; Gao, Chengde; Li, Yageng et al.
System: The UNT Digital Library
Dominant Role of Hole Transport Pathway in Achieving Record High Photoconductivity in Two-Dimensional Metal-Organic Frameworks (open access)

Dominant Role of Hole Transport Pathway in Achieving Record High Photoconductivity in Two-Dimensional Metal-Organic Frameworks

Article describes how metal-organic frameworks with mobile charges have attracted significant attention due to their potential application in photoelectric devices, chemical resistance sensors, and catalysis. The authors report the mechanisms of photoinduced charge transport and electron dynamics in the conductive 2D M−HHTP MOFs and their correlation with photoconductivity using the combination of time-resolved terahertz spectroscopy, optical transient absorption spectroscopy, X-ray transient absorption spectroscopy, and density functional theory calculations.
Date: October 23, 2023
Creator: Wang, Denan; Ostresh, Sarah; Streater, Daniel; He, Peilei; Nyakuchena, James; Ma, Qiushi et al.
System: The UNT Digital Library