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Evaluation of the Vibration Signal during Milling Vertical Thin-Walled Structures from Aerospace Materials (open access)

Evaluation of the Vibration Signal during Milling Vertical Thin-Walled Structures from Aerospace Materials

Article describes how the main functions of thin-walled structures are to reduce the weight of the finished product and to increase the rigidity of the structure. The authors compared the vibration signal for different approaches to machining thin walled-components with vertical walls made of Ti6AI4V titanium alloy and Inconel 625 nickel alloy.
Date: July 14, 2023
Creator: Kurpiel, Szymon; Zagrórski, Krzysztof; Skryzpkowski, Krzysztof & Brostow, Witold, 1934-
Object Type: Article
System: The UNT Digital Library
Enhanced Photoluminescence and Prolonged Carrier Lifetime through Laser Radiation Hardening and Self-Healing in Aged MAPbBr3 Perovskites Encapsulated in NiO Nanotubes (open access)

Enhanced Photoluminescence and Prolonged Carrier Lifetime through Laser Radiation Hardening and Self-Healing in Aged MAPbBr3 Perovskites Encapsulated in NiO Nanotubes

Article describes how organic-inorganic perovskites hold great promise as optoelectronic semiconductors for pure color light emitting and photovoltaic devices. This paper investigates the laser radiation hardening and self-healing-induced properties of aged MAPbBr3 perovskites encapsulated in NiO nanotubes (MAPbBr3@NiO) using photoluminescence (PL) and fluorescence lifetime imaging (FLIM). After deliberately subjecting the MAPbBr3@ NiO to atmospheric conditions for two years, the sample remains remarkably stable.
Date: August 31, 2023
Creator: Kamau, Steve; Rodriguez, Roberto Gonzalez; Jiang, Yan; Mondragon, Araceli Herrera; Varghese, Sinto; Hurley, Noah et al.
Object Type: Article
System: The UNT Digital Library
Holographic Fabrication of 3D Moiré Photonic Crystals Using Circularly Polarized Laser Beams and a Spatial Light Modulator (open access)

Holographic Fabrication of 3D Moiré Photonic Crystals Using Circularly Polarized Laser Beams and a Spatial Light Modulator

The authors of the article state that holographic fabrication of a 3D moiré photonic crystal is very difficult due to the coexistence of the bright and dark regions, where the exposure threshold is suitable for one region but not for the other. In this paper, the authors study the holographic fabrication of 3D moiré photonic crystals using an integrated system of a single reflective optical element (ROE) and a spatial light modulator (SLM) where nine beams (four inner beams + four outer beams + central beam) are overlapped.
Date: June 9, 2023
Creator: Hurley, Noah; Kamau, Steve; Cui, Jingbiao & Lin, Yuankun
Object Type: Article
System: The UNT Digital Library
The universal shape of the X-ray variability power spectrum of AGN up to z ∼ 3 (open access)

The universal shape of the X-ray variability power spectrum of AGN up to z ∼ 3

Authors of the article assert that they studied the ensemble X-ray variability properties of active galactic nuclei (AGN) over large ranges of timescale (20 ks ≤ T ≤ 14 yr), redshift (0 ≤ z ≲ 3), luminosity (1040 erg s−1 ≤ LX ≤ 1046 erg s−1), and black hole (BH) mass (106 ≤ M⊙ ≤ 109). The authors show that the data collected from archival observations and previous literature studies are fully consistent with a universal PSD form, which does not show any evidence for systematic evolution of shape or amplitude with redshift or luminosity, even if there may be differences between individual AGN at a given redshift or luminosity.
Date: May 8, 2023
Creator: Paolillo, Maurizio; Papadakis, I.; Brandt, William Nielsen; Bauer, Franz E.; Lanzuisi, G.; Allevato, V. et al.
Object Type: Article
System: The UNT Digital Library
X-Ray Unveiling Events in a z ≈ 1.6 Active Galactic Nucleus in the 7 Ms Chandra Deep Field-South (open access)

X-Ray Unveiling Events in a z ≈ 1.6 Active Galactic Nucleus in the 7 Ms Chandra Deep Field-South

Authors of the article explain that they investigated the extreme X-ray variability of a z = 1.608 active galactic nucleus in the 7 Ms Chandra Deep Field-South (XID 403), which showed two significant X-ray brightening events.
Date: May 18, 2023
Creator: Yu, Li-Ming; Luo, Bin; Brandt, William Nielsen; Bauer, Franz E.; De Cicco, D.; Fabian, Andrew C. et al.
Object Type: Article
System: The UNT Digital Library
Gemini Near Infrared Spectrograph–Distant Quasar Survey: Augmented Spectroscopic Catalog and a Prescription for Correcting UV-based Quasar Redshifts (open access)

Gemini Near Infrared Spectrograph–Distant Quasar Survey: Augmented Spectroscopic Catalog and a Prescription for Correcting UV-based Quasar Redshifts

Article describes how quasars at z ≳ 1 most often have redshifts measured from rest-frame ultraviolet emission lines. One of the most common such lines, C ivλ1549, shows blueshifts up to ≈5000 km s−1 and in rare cases even higher. The authors present spectroscopic measurements for 260 sources at 1.55 ≲ z ≲ 3.50 having −28.0 ≲ Mi ≲ − 30.0 mag from the Gemini Near Infrared Spectrograph–Distant Quasar Survey (GNIRS-DQS) catalog, augmenting the previous iteration, which contained 226 of the 260 sources whose measurements are improved upon in this work.
Date: June 13, 2023
Creator: Matthews, Brandon M.; Dix, Cooper; Shemmer, Ohad; Brotherton, Michael S.; Myers, Adam D.; Andruchow, I. et al.
Object Type: Article
System: The UNT Digital Library
Code Comparison in Galaxy-scale Simulations with Resolved Supernova Feedback: Lagrangian versus Eulerian Methods (open access)

Code Comparison in Galaxy-scale Simulations with Resolved Supernova Feedback: Lagrangian versus Eulerian Methods

Authors of the article present a suite of high-resolution simulations of an isolated dwarf galaxy using four different hydrodynamical codes: Gizmo, Arepo, Gadget, and Ramses. They find reasonable agreement on the time-averaged star formation rates as well as the joint density–temperature distributions between all codes.
Date: June 16, 2023
Creator: Hu, Chia-Yu; Smith, Matthew C.; Teyssier, Romain; Bryan, Greg L.; Verbeke, Robbert; Emerick, Andrew et al.
Object Type: Article
System: The UNT Digital Library
Shedding New Light on Weak Emission-Line Quasars in the CIV-Hβ Parameter Space (open access)

Shedding New Light on Weak Emission-Line Quasars in the CIV-Hβ Parameter Space

Article describes how weak emission-line quasars (WLQs) are a subset of Type 1 quasars that exhibit extremely weak Lyα+N V λ1240 and/or C IV λ1549 emission lines. The authors investigate the relationship between emission-line properties and accretion rate for a sample of 230 `ordinary' Type 1 quasars and 18 WLQs at z<0.5 and 1.5<z<3.5 that have rest-frame ultraviolet and optical spectral measurements.
Date: April 10, 2023
Creator: Ha, Trung; Dix, Cooper; Matthews, Brandon M.; Shemmer, Ohad; Brotherton, Michael S.; Myers, Adam D. et al.
Object Type: Article
System: The UNT Digital Library
Gemini Near Infrared Spectrograph–Distant Quasar Survey: Prescriptions for Calibrating UV-based Estimates of Supermassive Black Hole Masses in High-redshift Quasars (open access)

Gemini Near Infrared Spectrograph–Distant Quasar Survey: Prescriptions for Calibrating UV-based Estimates of Supermassive Black Hole Masses in High-redshift Quasars

Article describes how the most reliable single-epoch supermassive black hole mass (MBH) estimates in quasars are obtained by using the velocity widths of low-ionization emission lines, typically the Hβλ4861 line. The authors find that utilizing both emission lines, where available, reduces the scatter of UV-based MBH estimates by ∼15% when compared to previous studies.
Date: June 13, 2023
Creator: Dix, Cooper; Matthews, Brandon; Shemmer, Ohad; Brotherton, Michael S.; Myers, Adam D.; Andruchow, I. et al.
Object Type: Article
System: The UNT Digital Library
Temporal complexity measure of reaction time series: Operational versus event time (open access)

Temporal complexity measure of reaction time series: Operational versus event time

Article describes how detrended fluctuation analysis (DFA) is a well-established method to evaluate scaling indices of time series, which categorize the dynamics of complex systems. The authors propose treating each reaction time as a duration time that changes the representation from operational (trial number) time n to event (temporal) time t, or X(t).
Date: May 23, 2023
Creator: Mahmoodi, Korosh; Kerick, Scott E.; Grigolini, Paolo; Franaszczuk, Pitor J. & West, Bruce J.
Object Type: Article
System: The UNT Digital Library
Uncoupling system and environment simulation cells for fast-scaling modeling of complex continuum embeddings (open access)

Uncoupling system and environment simulation cells for fast-scaling modeling of complex continuum embeddings

Article describes how continuum solvation models are becoming increasingly relevant in condensed matter simulations, allowing to characterize materials interfaces in the presence of wet electrified environments at a reduced computational cost with respect to all atomistic simulations. However, some challenges with the implementation of these models in plane-wave simulation packages still persists, and to address these challenges, the authors present the implementation of a double-cell formalism, in which the simulation cell used for the continuum environment is uncoupled from the one used for the electronic-structure simulation of the quantum-mechanical system.
Date: August 1, 2023
Creator: Medrano, G.; Bainglass, E. & Andreussi, O.
Object Type: Article
System: The UNT Digital Library
Optical Pump Terahertz Probe (OPTP) and Time Resolved Terahertz Spectroscopy (TRTS) of emerging solar materials Editor’s Pick (open access)

Optical Pump Terahertz Probe (OPTP) and Time Resolved Terahertz Spectroscopy (TRTS) of emerging solar materials Editor’s Pick

Article describes how photoconductivity is the crucial benchmark to assess the potential of any emerging material for future solar applications. This tutorial aims to familiarize the reader with the main THz techniques used to explore emerging materials.
Date: July 19, 2023
Creator: Neu, Jens
Object Type: Article
System: The UNT Digital Library
Quantum algorithm for electronic band structures with local tight-binding orbitals (open access)

Quantum algorithm for electronic band structures with local tight-binding orbitals

Article says that while the main thrust of quantum computing research in materials science is to accurately measure the classically intractable electron correlation effects due to Coulomb repulsion, designing optimal quantum algorithms for simpler problems with well-understood solutions is a useful tactic to advance our quantum “toolbox”. In this paper, the authors adopt a direct space approach, using a novel hybrid first/second-quantized qubit mapping which allows us to construct a single Hamiltonian, and a single cost-function, suitable for solving the entire electronic band structure.
Date: June 14, 2022
Creator: Sherbert, Kyle; Jayaraj, Anooja & Buongiorno Nardelli, Marco
Object Type: Article
System: The UNT Digital Library
Automated Approach to In Vitro Image-Guided Photothermal Therapy with Top-Down and Bottom-Up-Synthesized Graphene Quantum Dots (open access)

Automated Approach to In Vitro Image-Guided Photothermal Therapy with Top-Down and Bottom-Up-Synthesized Graphene Quantum Dots

Article discusses how, based on recent studies, graphene quantum dots (GQDs) are expected to possess advantageous photothermal properties and facilitate fluorescence image-tracking in the visible and near-infrared (NIR), while surpassing other graphene-based materials in their biocompatibility. The combination of the photothermal and imaging modalities tested in vitro makes the GQDs developed in this work prospective agents for cancer theragnostics.
Date: February 22, 2023
Creator: Lee, Bong; Stokes, Gretel A.; Valimukhametova, Alina; Nguyen, Steven; Gonzalez-Rodriguez, Roberto; Bhaloo, Adam et al.
Object Type: Article
System: The UNT Digital Library
Long-range current-induced spin accumulation in chiral crystals (open access)

Long-range current-induced spin accumulation in chiral crystals

Article states that chiral materials, similarly to human hands, have distinguishable right-handed and left-handed enantiomers which may behave differently in response to external stimuli, so for the first time the authors use an approach based on the density functional theory (DFT)+PAOFLOW calculations to quantitatively estimate the so-called collinear Rashba–Edelstein effect (REE) that generates spin accumulation parallel to charge current and can manifest as chirality-dependent charge-to-spin conversion in chiral crystals. The authors reveal that the spin accumulation induced in the bulk by an electric current is intrinsically protected by the quasi-persistent spin helix arising from the crystal symmetries present in chiral systems with the Weyl spin–orbit coupling.
Date: November 18, 2022
Creator: Roy, Arunesh; Cerasoli, Frank T.; Jayaraj, Anooja; Tenzin, Karma; Buongiorno Nardelli, Marco & Sławińska, Jagoda
Object Type: Article
System: The UNT Digital Library
Tuning the decay of sound in a viscous metamaterial (open access)

Tuning the decay of sound in a viscous metamaterial

Authors of the article use analytical results for viscous dissipation in phononic crystals to calculate the decay coefficient of a sound wave propagating at low frequencies through a two-dimensional phononic crystal with a viscous fluid background. They claim that the decay coefficient exhibits dependence on the direction of propagation; that is, a homogenized phononic crystal behaves like an anisotropic viscous fluid.
Date: October 10, 2022
Creator: Ibarias, M.; Doporto, J.; Krokhin, Arkadii A. & Arriaga, J.
Object Type: Article
System: The UNT Digital Library
Growth of Highly-Ordered Metal Nanoparticle Arrays in the Dimpled Pores of an Anodic Aluminum Oxide Template (open access)

Growth of Highly-Ordered Metal Nanoparticle Arrays in the Dimpled Pores of an Anodic Aluminum Oxide Template

Article presents a reliable, scalable, and inexpensive technology for the fabrication of ordered arrays of metal nanoparticles with large areal coverage on various substrates. Using a simple model, the experimental results were interpreted and supported by numerical estimations.
Date: November 8, 2022
Creator: Farmer, Gavin; Abraham, James; Littler, Chris; Syllaios, A. J. & Philipose, Usha
Object Type: Article
System: The UNT Digital Library
Analyzing the Bolometric Performance of Vanadium Oxide Thin Films Modified by Carbon Nanotube Dispersions (open access)

Analyzing the Bolometric Performance of Vanadium Oxide Thin Films Modified by Carbon Nanotube Dispersions

Article investigates the influence of carbon nanotube (CNT) dispersions on the electrical properties and noise signal amplitude of 𝑉𝑂𝑥 films. The results presented in this work provide a better understanding of 𝑉𝑂𝑥-based composites, thereby enabling the development of new, versatile and functional materials for device applications.
Date: February 12, 2023
Creator: Philipose, Usha; Littler, Chris; Jiang, Yan; Naciri, Alia; Harcrow, Michael & Syllaios, A. J.
Object Type: Article
System: The UNT Digital Library
Evolutionary models of lateralization: Steps toward stigmergy? (open access)

Evolutionary models of lateralization: Steps toward stigmergy?

Article discusses an interesting approach to accounting for brain and behavioral asymmetry based on competition and cooperation in phenotypically asymmetric individuals. The model in question shows, in an almost fully analytical way, that under proper conditions, there exists an unequal number of equilibrium of left-and right-lateralized individuals.
Date: February 2, 2023
Creator: Tonello, Lucio & Vallortigara, Giorgio
Object Type: Article
System: The UNT Digital Library
Unusual Mathematical Approaches Untangle Nervous Dynamics (open access)

Unusual Mathematical Approaches Untangle Nervous Dynamics

Article reports that the massive amount of available neurodata suggests the existence of a mathematical backbone underlying neuronal oscillatory activities. The authors assert that the Monge’s theorem might contribute to our visual ability of depth perception and the brain connectome can be tackled in terms of tunnelling nanotubes.
Date: October 14, 2022
Creator: Tozzi, Arturo & Mariniello, Lucio
Object Type: Article
System: The UNT Digital Library
An X-ray fading, UV brightening QSO at z ≈ 6 (open access)

An X-ray fading, UV brightening QSO at z ≈ 6

Article presents quasi-simultaneous X-ray and rest-frame UV observations of quasi-stellar object (QSO) z = 6.025 QSO J1641+3755.
Date: July 26, 2022
Creator: Vito, F.; Mignoli, M.; Gilli, R.; Brandt, William Nielsen; Shemmer, Ohad; Bauer, Franz E. et al.
Object Type: Article
System: The UNT Digital Library
Weakly Aligned Molecules: From Molecular Detectors to Room-Temperature Tunable Masers (open access)

Weakly Aligned Molecules: From Molecular Detectors to Room-Temperature Tunable Masers

Conference proceeding presenting a new mechanism of manipulation of population in molecular rotational levels in a weakly aligned molecules. Originally presented as an invited talk at the 29th International Laser Physics Workshop held July 19-23, 2021.
Date: July 23, 2021
Creator: Roy, Colin D.; Branković, Zorica & Rostovtsev, Yuri V.
Object Type: Article
System: The UNT Digital Library
Exploring Changes in Quasar Spectral Energy Distributions across C iv Parameter Space (open access)

Exploring Changes in Quasar Spectral Energy Distributions across C iv Parameter Space

This article examines the UV/X-ray properties of 1378 quasars in order to link empirical correlations to theoretical models of the physical mechanisms dominating quasars as a function of mass and accretion rate.
Date: June 6, 2022
Creator: Rivera, Angelica B.; Richards, Gordon T.; Gallagher, Sarah C.; McCaffrey, Trevor V.; Rankine, Amy L.; Hewett, Paul C. et al.
Object Type: Article
System: The UNT Digital Library
Can X-Ray Observations Improve Optical-UV-based Accretion-rate Estimates for Quasars? (open access)

Can X-Ray Observations Improve Optical-UV-based Accretion-rate Estimates for Quasars?

Article presents a study utilizing a carefully selected sample of 53 radio-quiet quasars that have Hβ and C iv λ1549 spectroscopy as well as Chandra coverage, to search for a robust accretion-rate indicator for quasars, particularly at the highest-accessible redshifts (z ∼ 6–7).
Date: May 23, 2022
Creator: Marlar, Andrea
Object Type: Article
System: The UNT Digital Library