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Materials Science and Engineering
Materials Science and Engineering Faculty Publications and Presentations
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- Chemistry (4)
- Electrical Engineering (4)
- Physics (4)
- Atomic force microscopy (3)
- Additive manufacturing (2)
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- Atomic layer deposition (2)
- Chemical structure (2)
- Genetics (2)
- Mechanical Engineering (2)
- 3D printing (1)
- Ab-initio molecular dynamics (1)
- Actuator (1)
- Adsorption/gas (1)
- Advanced manufacturing (1)
- Aerosol jet printing (1)
- Alloys (1)
- Alumina (1)
- BRC (1)
- Biology (1)
- Chromium (1)
- Computer Science (1)
- Computer simulations (MC and MD) (1)
- Corrosion (1)
- Crystal mosaicity (1)
- Crystallographic defects (1)
- Cy5 (1)
- Cyanine dye (1)
- DNA computing and cryptography (1)
- DNA nanostructures (1)
- DRED (1)
Articles 1 - 26 of 26
Full-Text Articles in Engineering
A Comparison Of Solid Electrolyte Interphase Formation And Evolution On Highly Oriented Pyrolytic And Disordered Graphite Negative Electrodes In Lithium-Ion Batteries, Haoyu Zhu, Joshua A. Russell, Zongtang Fang, Pete Barnes, Lan Li, Corey M. Efaw, Allison Muenzer, Jeremy May, Kailash Hamal, I. Francis Cheng, Paul H. Davis, Eric J. Dufek, Hui Xiong
A Comparison Of Solid Electrolyte Interphase Formation And Evolution On Highly Oriented Pyrolytic And Disordered Graphite Negative Electrodes In Lithium-Ion Batteries, Haoyu Zhu, Joshua A. Russell, Zongtang Fang, Pete Barnes, Lan Li, Corey M. Efaw, Allison Muenzer, Jeremy May, Kailash Hamal, I. Francis Cheng, Paul H. Davis, Eric J. Dufek, Hui Xiong
Materials Science and Engineering Faculty Publications and Presentations
The presence and stability of solid electrolyte interphase (SEI) on graphitic electrodes is vital to the performance of lithium-ion batteries (LIBs). However, the formation and evolution of SEI remain the least understood area in LIBs due to its dynamic nature, complexity in chemical composition, heterogeneity in morphology, as well as lack of reliable in situ/operando techniques for accurate characterization. In addition, chemical composition and morphology of SEI are not only affected by the choice of electrolyte, but also by the nature of the electrode surface. While introduction of defects into graphitic electrodes has promoted their electrochemical properties, how such structural …
Tensile-Strained Self-Assembly Of Ingaas On Inas(111)A, Kevin D. Vallejo, Trent A. Garrett, Carlos I. Cabrera, Baolai Liang, Kevin A. Grossklaus, Paul J. Simmonds
Tensile-Strained Self-Assembly Of Ingaas On Inas(111)A, Kevin D. Vallejo, Trent A. Garrett, Carlos I. Cabrera, Baolai Liang, Kevin A. Grossklaus, Paul J. Simmonds
Materials Science and Engineering Faculty Publications and Presentations
We have determined a reproducible set of growth conditions for the self-assembly of tensile-strained In1-xGaxAs quantum dot (QD) nanostructures on (111)A surfaces. During molecular beam epitaxy, In1-xGaxAs islands form spontaneously on InAs(111)A when the Ga content x ≥ 50%. We analyze the structure and composition of InGaAs/InAs(111) samples using atomic force microscopy, transmission electron microscopy, and electron energy loss spectroscopy. We demonstrate control over the size and areal density of the islands as a function of In1-xGaxAs coverage, In1-xGaxAs composition, …
Spatial And Temporal Analysis Of Sodium-Ion Batteries, Dewen Hou, Eric Gabriel, Joshua A. Russell, Kincaid Graff, Hui Xiong
Spatial And Temporal Analysis Of Sodium-Ion Batteries, Dewen Hou, Eric Gabriel, Joshua A. Russell, Kincaid Graff, Hui Xiong
Materials Science and Engineering Faculty Publications and Presentations
As a promising alternative to the market-leading lithium-ion batteries, low-cost sodium-ion batteries (SIBs) are attractive for applications such as large-scale electrical energy storage systems. The energy density, cycling life, and rate performance of SIBs are fundamentally dependent on dynamic physiochemical reactions, structural change, and morphological evolution. Therefore, it is essential to holistically understand SIBs reaction processes, degradation mechanisms, and thermal/mechanical behaviors in complex working environments. The recent developments of advanced in situ and operando characterization enable the establishment of the structure–processing–property–performance relationship in SIBs under operating conditions. This Review summarizes significant recent progress in SIBs exploiting in situ and operando …
Additive Manufacturing Of Miniaturized Peak Temperature Monitors For In-Pile Applications, Kiyo T. Fujimoto, Yaqiao Wu, David Estrada
Additive Manufacturing Of Miniaturized Peak Temperature Monitors For In-Pile Applications, Kiyo T. Fujimoto, Yaqiao Wu, David Estrada
Materials Science and Engineering Faculty Publications and Presentations
Passive monitoring techniques have been used for peak temperature measurements during irradiation tests by exploiting the melting point of well-characterized materials. Recent efforts to expand the capabilities of such peak temperature detection instrumentation include the development and testing of additively manufactured (AM) melt wires. In an effort to demonstrate and benchmark the performance and reliability of AM melt wires, we conducted a study to compare prototypical standard melt wires to an AM melt wire capsule, composed of printed aluminum, zinc, and tin melt wires. The lowest melting-point material used was Sn, with a melting point of approximately 230 °C, Zn …
Customizable Aptamer Transducer Network Designed For Feed-Forward Coupling, Tim Hachigian, Drew Lysne, Elton Graugnard, Jeunghoon Lee
Customizable Aptamer Transducer Network Designed For Feed-Forward Coupling, Tim Hachigian, Drew Lysne, Elton Graugnard, Jeunghoon Lee
Materials Science and Engineering Faculty Publications and Presentations
Solution-based biosensors that utilize aptamers have been engineered in a variety of formats to detect a range of analytes for both medical and environmental applications. However, since aptamers have fixed base sequences, incorporation of aptamers into DNA strand displacement networks for feed-forward signal amplification and processing requires significant redesign of downstream DNA reaction networks. We designed a novel aptamer transduction network that releases customizable output domains, which can then be used to initiate downstream strand displacement reaction networks without any sequence redesign of the downstream reaction networks. In our aptamer transducer (AT), aptamer input domains are independent of output domains …
Excited-State Lifetimes Of Dna-Templated Cyanine Dimer, Trimer, And Tetramer Aggregates: The Role Of Exciton Delocalization, Dye Separation, And Dna Heterogeneity, Jonathan S. Huff, Daniel B. Turner, Olga A. Mass, Lance K. Patten, Christopher K. Wilson, Simon K. Roy, Matthew S. Barclay, Bernard Yurke, William B. Knowlton, Paul H. Davis, Ryan D. Pensack
Excited-State Lifetimes Of Dna-Templated Cyanine Dimer, Trimer, And Tetramer Aggregates: The Role Of Exciton Delocalization, Dye Separation, And Dna Heterogeneity, Jonathan S. Huff, Daniel B. Turner, Olga A. Mass, Lance K. Patten, Christopher K. Wilson, Simon K. Roy, Matthew S. Barclay, Bernard Yurke, William B. Knowlton, Paul H. Davis, Ryan D. Pensack
Materials Science and Engineering Faculty Publications and Presentations
DNA-templated molecular (dye) aggregates are a novel class of materials that have garnered attention in a broad range of areas including light harvesting, sensing, and computing. Using DNA to template dye aggregation is attractive due to the relative ease with which DNA nanostructures can be assembled in solution, the diverse array of nanostructures that can be assembled, and the ability to precisely position dyes to within a few Angstroms of one another. These factors, combined with the programmability of DNA, raise the prospect of designer materials custom tailored for specific applications. Although considerable progress has been made in characterizing the …
First-Principles Magnetic Treatment Of The Uranium Nitride (100) Surface And Effect On Corrosion Initiation, Ember L. Sikorski, Brian J. Jaques, Lan Li
First-Principles Magnetic Treatment Of The Uranium Nitride (100) Surface And Effect On Corrosion Initiation, Ember L. Sikorski, Brian J. Jaques, Lan Li
Materials Science and Engineering Faculty Publications and Presentations
The magnetic properties of uranium nitride (UN) surfaces are not well understood experimentally or computationally but they have a significant effect on UN performance as a nuclear fuel. We investigated ferromagnetic (FM), antiferromagnetic (AFM), nonmagnetic (NM), and three hybrid magnetic structures of the most stable UN surface (100). To account for electron correlation and metastability, a U-ramp was performed to an effective Hubbard U-term of 2.0 eV. FM was found to be the most energetically favorable magnetic structure. Type 1 AFM slab was optimized to a new magnetic structure consisting of (100) planes with either all spin-up electrons, all spin-down …
Laser-Defined Graphene Strain Sensor Directly Fabricated On 3d-Printed Structure, Tyler M. Webb, Twinkle Pandhi, David Estrada
Laser-Defined Graphene Strain Sensor Directly Fabricated On 3d-Printed Structure, Tyler M. Webb, Twinkle Pandhi, David Estrada
Materials Science and Engineering Faculty Publications and Presentations
A direct-write method to fabricate a strain sensor directly on a structure of interest is reported. In this method, a commercial graphene ink is printed as a square patch (6 mm square) on the structure. The patch is dried at 100 °C for 30 min to remove residual solvents but the printed graphene remains in an insulative state. By scanning a focused laser (830 nm, 100 mW), the graphene becomes electrically conductive and exhibits a piezoresistive effect and a low temperature coefficient of resistance of −0.0006 °C−1. Using this approach, the laser defines a strain sensor pattern on …
Effect Of Crystal Quality On Twinning Stress In Ni–Mn–Ga Magnetic Shape Memory Alloys, Andrew Armstrong, Peter Müllner
Effect Of Crystal Quality On Twinning Stress In Ni–Mn–Ga Magnetic Shape Memory Alloys, Andrew Armstrong, Peter Müllner
Materials Science and Engineering Faculty Publications and Presentations
Low twinning stress (TS) is a prerequisite for magnetic shape memory functionality in ferromagnetic martensites. We compare Ni50Mn28Ga22 (nominal at.%) single crystals from four different producers to reveal the effect of crystal quality on the TS. Near the reverse martensite transformation, the TS is generally low, about 1 MPa, regardless of mosaicity of up to 1.7° and chemical composition deviations of up to 2 at.% of Mn. Pure type I and type II twin boundaries occur in crystals with smooth chemical composition gradients. The corresponding temperature dependences of TS follow universal linear trends with the …
Microstructure And Microchemistry Of Laser Welds Of Irradiated Austenitic Steels, Yaqiao Wu, Megha Dubey
Microstructure And Microchemistry Of Laser Welds Of Irradiated Austenitic Steels, Yaqiao Wu, Megha Dubey
Materials Science and Engineering Faculty Publications and Presentations
This article investigates the integrity of laser welds on neutron irradiated, He-containing steels. Life extension of the current fleet of light water reactors could necessitate repair of cracks on irreplaceable internal components, but heat input of weld repairs exacerbates the problem by initiating He-induced cracking. Laser welding is a promising low-heat-input technology thought to limit the extent of He-induced cracking. In this study, we produce laser welds in a hot cell on AISI 304L stainless steel plates previously irradiated in the Experimental Breeder Reactor (EBR)-II. We select a systematic set of three specimens spanning fluences ~1–28 displacements per atom (dpa) …
Role Of Lithium Doping In P2-Na0.67Ni0.33Mn0.67O2 For Sodium-Ion Batteries, Yingying Xie, Eric Gabriel, Haoyu Zhu, Julie Pipkin, Malia Dustin, Hui Xiong
Role Of Lithium Doping In P2-Na0.67Ni0.33Mn0.67O2 For Sodium-Ion Batteries, Yingying Xie, Eric Gabriel, Haoyu Zhu, Julie Pipkin, Malia Dustin, Hui Xiong
Materials Science and Engineering Faculty Publications and Presentations
P2-structured Na0.67Ni0.33Mn0.67O2 (PNNMO) is a promising Na-ion battery cathode material, but its rapid capacity decay during cycling remains a hurdle. Li doping in layered transition-metal oxide (TMO) cathode materials is known to enhance their electrochemical properties. Nevertheless, the influence of Li at different locations in the structure has not been investigated. Here, the crystallographic role and electrochemical impact of lithium on different sites in PNNMO is investigated in LixNa0.67–yNi0.33Mn0.67O2+δ (0.00 ≤ x ≤ 0.2, y = 0, 0.1). Lithium occupancy on prismatic Na …
First-Principles Studies Of Substituent Effects On Squaraine Dyes, German Barcenas, Austin Biaggne, Olga A. Mass, Christopher K. Wilson, Ryan D. Pensack, Jeunghoon Lee, William B. Knowlton, Bernard Yurke, Lan Li
First-Principles Studies Of Substituent Effects On Squaraine Dyes, German Barcenas, Austin Biaggne, Olga A. Mass, Christopher K. Wilson, Ryan D. Pensack, Jeunghoon Lee, William B. Knowlton, Bernard Yurke, Lan Li
Materials Science and Engineering Faculty Publications and Presentations
Dye molecules that absorb light in the visible region are key components in many applications, including organic photovoltaics, biological fluorescent labeling, super-resolution microscopy, and energy transport. One family of dyes, known as squaraines, has received considerable attention recently due to their favorable electronic and photophysical properties. In addition, these dyes have a strong propensity for aggregation, which results in emergent materials properties, such as exciton delocalization. This will be of benefit in charge separation and energy transport along with fundamental studies in quantum information. Given the high structural tunability of squaraine dyes, it is possible that exciton delocalization could be …
Ball-On-Ring Test Validation For Equibiaxial Flexural Strength Testing Of Engineered Ceramics, Adrianna E. Lupercio, Ehsan Moshkelgosha, Riley C. Winters, Cayden Doyle, Mahmood Mamivand, Andrew T. Nelson, Brian J. Jaques
Ball-On-Ring Test Validation For Equibiaxial Flexural Strength Testing Of Engineered Ceramics, Adrianna E. Lupercio, Ehsan Moshkelgosha, Riley C. Winters, Cayden Doyle, Mahmood Mamivand, Andrew T. Nelson, Brian J. Jaques
Materials Science and Engineering Faculty Publications and Presentations
The validation of a ball-on-ring, equibiaxial flexural strength method to obtain the transverse rupture strength (TRS) of right cylindrical ceramic specimens was performed in this study. Validation of the test method was achieved using commercially available engineered high purity alumina disks and finite element (FE) model analysis. The validated fixture was then used to obtain the TRS and Weibull statistical analysis of MgO-partially stabilized zirconia (MSZ) and Y2O3-partially stabilized zirconia (YSZ) ceramic disks. TRS data for alumina, MSZ, and YSZ agreed with the TRS values reported in the literature. A statistically relevant number of samples (N …
Atomic Layer Deposition Of Sodium Fluoride Thin Films, Sara Kuraitis, Donghyeon Kang, Anil U. Mane, Hua Zhou, Jake Soares, Jeffrey W. Elam, Elton Graugnard
Atomic Layer Deposition Of Sodium Fluoride Thin Films, Sara Kuraitis, Donghyeon Kang, Anil U. Mane, Hua Zhou, Jake Soares, Jeffrey W. Elam, Elton Graugnard
Materials Science and Engineering Faculty Publications and Presentations
The need for advanced energy conversion and storage devices remains a critical challenge amid the growing worldwide demand for renewable energy. Metal fluoride thin films are of great interest for applications in lithium-ion and emerging rechargeable battery technologies, particularly for enhancing the stability of the electrode-electrolyte interface and thereby extending battery cyclability and lifetime. Reported within, sodium fluoride (NaF) thin films were synthesized via atomic layer deposition (ALD). NaF growth experiments were carried out at reactor temperatures between 175 and 250 °C using sodium tert-butoxide and HF-pyridine solution. The optimal deposition temperature range was 175–200 °C, and the resulting …
An Alternative Approach To Nucleic Acid Memory, George D. Dickinson, Golam Md Mortuza, William Clay, Luca Piantanida, Christopher M. Green, Chad Watson, Eric J. Hayden, Tim Andersen, Wan Kuang, Elton Graugnard, Reza Zadegan, William L. Hughes
An Alternative Approach To Nucleic Acid Memory, George D. Dickinson, Golam Md Mortuza, William Clay, Luca Piantanida, Christopher M. Green, Chad Watson, Eric J. Hayden, Tim Andersen, Wan Kuang, Elton Graugnard, Reza Zadegan, William L. Hughes
Materials Science and Engineering Faculty Publications and Presentations
DNA is a compelling alternative to non-volatile information storage technologies due to its information density, stability, and energy efficiency. Previous studies have used artificially synthesized DNA to store data and automated next-generation sequencing to read it back. Here, we report digital Nucleic Acid Memory (dNAM) for applications that require a limited amount of data to have high information density, redundancy, and copy number. In dNAM, data is encoded by selecting combinations of single-stranded DNA with (1) or without (0) docking-site domains. When self-assembled with scaffold DNA, staple strands form DNA origami breadboards. Information encoded into the breadboards is read by …
Actuating A Magnetic Shape Memory Element Locally With A Set Of Coils, Andrew Armstrong, Peter Müllner
Actuating A Magnetic Shape Memory Element Locally With A Set Of Coils, Andrew Armstrong, Peter Müllner
Materials Science and Engineering Faculty Publications and Presentations
The local actuation of a magnetic shape memory (MSM) element as used in an MSM micropump is considered. This paper presents the difference between an electromagnetic driver and a driver that uses a rotating permanent magnet. For the magnetic field energy of the permanent magnetic drive, the element takes in a significant stray field. In a particular case, energy reduction was 12.7 mJ. For an electromagnetic drive with an identical size of the MSM element, the total magnetic field energy created by the system was 2.28 mJ. Attempts to experimentally nucleate twins in an MSM element by energizing an electromagnetic …
Adsorption And Surface Diffusion Of Metals On Α-Al2O3 For Advanced Manufacturing Applications, Austin Biaggne, Gregory Noble, Lan Li
Adsorption And Surface Diffusion Of Metals On Α-Al2O3 For Advanced Manufacturing Applications, Austin Biaggne, Gregory Noble, Lan Li
Materials Science and Engineering Faculty Publications and Presentations
The adsorption and diffusion of Mo and Nb adatoms on the α-Al2O3 (0001) surface were explored using density functional theory-based methods. Adsorption energies of Mo and Nb adatoms at minima sites on the surface were determined. Mo and Nb adatoms prefer to adsorb to the same locations on the surface, and larger adsorption energies calculated for Nb compared to Mo indicate that Nb adatom-surface interactions are stronger than Mo. Using minima adsorption sites as initial and final locations for surface diffusion, energy barriers for diffusion were calculated using the nudged elastic band method. Overall, Mo and …
Signatures Of Vibrational And Electronic Quantum Beats In Femtosecond Coherence Spectra, Paul C. Arpin, Daniel B. Turner
Signatures Of Vibrational And Electronic Quantum Beats In Femtosecond Coherence Spectra, Paul C. Arpin, Daniel B. Turner
Materials Science and Engineering Faculty Publications and Presentations
Femtosecond laser pulses can produce oscillatory signals in transient-absorption spectroscopy measurements. The quantum beats are often studied using femtosecond coherence spectra (FCS), the Fourier domain amplitude, and phase profiles at individual oscillation frequencies. In principle, one can identify the mechanism that gives rise to each quantum-beat signal by comparing its measured FCS to those arising from microscopic models. To date, however, most measured FCS deviate from the ubiquitous harmonic oscillator model. Here, we expand the inventory of models to which the measured spectra can be compared. We develop quantum-mechanical models of the fundamental, overtone, and combination-band FCS arising from harmonic …
Interface Structure And Luminescence Properties Of Epitaxial Pbse Films On Inas(111)A, Kevin D. Vallejo, Paul J. Simmonds
Interface Structure And Luminescence Properties Of Epitaxial Pbse Films On Inas(111)A, Kevin D. Vallejo, Paul J. Simmonds
Materials Science and Engineering Faculty Publications and Presentations
Epitaxial heterostructures of narrow-gap IV-VI and III-V semiconductors offer a platform for new electronics and mid-infrared photonics. Stark dissimilarities in the bonding and the crystal structure between the rocksalt IV–VIs and the zincblende III–Vs, however, mandate the development of nucleation and growth protocols to reliably prepare high-quality heterostructures. In this work, we demonstrate a route to single crystal (111)-oriented PbSe epitaxial films on nearly lattice-matched InAs (111)A templates. Without this technique, the high-energy heterovalent interface readily produces two populations of PbSe grains that are rotated 180° in-plane with respect to each other, separated by rotational twin boundaries. We find that …
First-Principles Studies Of Mof Absorption On Hydroxylated And Non-Hydroxylated Metal Oxide Surfaces And Implications For Atomic Layer Deposition Of Mos2, Matthew Lawson, Elton Graugnard, Lan Li
First-Principles Studies Of Mof Absorption On Hydroxylated And Non-Hydroxylated Metal Oxide Surfaces And Implications For Atomic Layer Deposition Of Mos2, Matthew Lawson, Elton Graugnard, Lan Li
Materials Science and Engineering Faculty Publications and Presentations
Significant interest in two-dimensional transition metal dichalcogenides has led to numerous experimental studies of their synthesis using scalable vapor phase methods, such as chemical vapor deposition (CVD) and atomic layer deposition (ALD). ALD typically allows lower deposition temperatures, and nucleation of chemical precursors requires reactions with surface functional groups. A common first-principles method used to study ALD modeling is the calculation of activation energy for a proposed reaction pathway. In this work we calculated the partial charge densities, local density of states (LDoS), Bader charge analysis, adsorption energies, and charge density difference using density functional theory (DFT) to investigate the …
Open-Source Molecular Modeling Software In Chemical Engineering Focusing On The Molecular Simulation Design Framework, Eric Jankowski
Open-Source Molecular Modeling Software In Chemical Engineering Focusing On The Molecular Simulation Design Framework, Eric Jankowski
Materials Science and Engineering Faculty Publications and Presentations
Molecular simulation has emerged as an important sub-field of chemical engineering, due in no small part to the leadership of Keith Gubbins. A characteristic of the chemical engineering molecular simulation community is the commitment to freely share simulation codes and other key software components required to perform a molecular simulation under open-source licenses and distribution on public repositories such as GitHub. Here we provide an overview of opensource molecular modeling software in Chemical Engineering, with focus on the Molecular Simulation Design Framework (MoSDeF). MoSDeF is an open-source Python software stack that enables facile use of multiple open-source molecular simulation engines, …
A Macro-Scale Ruck And Tuck Mechanism For Deformation In Ion-Irradiated Polycrystalline Graphite, Steve Johns, Karthik Chinnathambi
A Macro-Scale Ruck And Tuck Mechanism For Deformation In Ion-Irradiated Polycrystalline Graphite, Steve Johns, Karthik Chinnathambi
Materials Science and Engineering Faculty Publications and Presentations
A vein structure, which becomes more pronounced with increasing ion dose, was found on the surface of polycrystalline HOPG (highly oriented pyrolytic graphite) implanted by ex situ C+ (up to 1.8x1017 ions/cm2), and in situ Ar+ in a transmission electron microscope (TEM). These veins are found to be independent of the crystallographic orientations and are associated with the formation of pores. Underneath the veins, a triangular-shaped core was formed with the graphite platelet inside the core displaced up towards the surface. A macro-scale ‘ruck&tuck’ geometry was thus generated at these triangle structure boundaries. Progressive movement …
Impact Of Grain Orientation And Phase On Volta Potential Differences In An Additively Manufactured Titanium Alloy, Jake T. Benzing, Olivia O. Maryon, Nik Hrabe, Paul H. Davis, Michael F. Hurley, Frank W. Delrio
Impact Of Grain Orientation And Phase On Volta Potential Differences In An Additively Manufactured Titanium Alloy, Jake T. Benzing, Olivia O. Maryon, Nik Hrabe, Paul H. Davis, Michael F. Hurley, Frank W. Delrio
Materials Science and Engineering Faculty Publications and Presentations
This work introduces a method for co-localized multi-modal imaging of sub-μm features in an additively manufactured (AM) titanium alloy. Ti-6Al-4V parts manufactured by electron beam melting powder bed fusion were subjected to hot isostatic pressing to seal internal porosity and machined to remove contour–hatch interfaces. Electron microscopy and atomic force microscopy-based techniques (electron backscatter diffraction and scanning Kelvin probe force microscopy) were used to measure and categorize the effects of crystallographic texture, misorientation, and phase content on the relative differences in the Volta potential of α-Ti and β-Ti phases. Given the tunability of additive manufacturing processes, …
Substituent Effects On The Solubility And Electronic Properties Of The Cyanine Dye Cy5: Density Functional And Time-Dependent Density Functional Theory Calculations, Austin Biaggne, William B. Knowlton, Bernard Yurke, Jeunghoon Lee, Lan Li
Substituent Effects On The Solubility And Electronic Properties Of The Cyanine Dye Cy5: Density Functional And Time-Dependent Density Functional Theory Calculations, Austin Biaggne, William B. Knowlton, Bernard Yurke, Jeunghoon Lee, Lan Li
Materials Science and Engineering Faculty Publications and Presentations
The aggregation ability and exciton dynamics of dyes are largely affected by properties of the dye monomers. To facilitate aggregation and improve excitonic function, dyes can be engineered with substituents to exhibit optimal key properties, such as hydrophobicity, static dipole moment differences, and transition dipole moments. To determine how electron donating (D) and electron withdrawing (W) substituents impact the solvation, static dipole moments, and transition dipole moments of the pentamethine indocyanine dye Cy5, density functional theory (DFT) and time-dependent (TD-) DFT calculations were performed. The inclusion of substituents had large effects on the solvation energy of Cy5, with pairs of …
Microstructural And Chemical Characterization Of A Purple Pigment From A Faiyum Mummy Portrait, Glenn Gates, Yaqiao Wu, Jatuporn Burns, Jennifer Watkins, Darryl P. Butt
Microstructural And Chemical Characterization Of A Purple Pigment From A Faiyum Mummy Portrait, Glenn Gates, Yaqiao Wu, Jatuporn Burns, Jennifer Watkins, Darryl P. Butt
Materials Science and Engineering Faculty Publications and Presentations
Results are presented from analyses that were conducted to explain the presence of chromium, detected noninvasively using energy-dispersive X-ray fluorescence (XRF), in the unusually large (2-3mm diameter) rough gem-like purple pigment particles in the paint used for a Faiyum mummy portrait. An approximately 50 μm diameter particle of the chromium-containing purple pigment was extracted from the Portrait of a Bearded Man, dated to Roman Imperial Egypt in the second century, circa 170-180 CE, accession #32.6 in the Walters Art Museum collection. The particle was characterized using energy-dispersive X-ray fluorescence analysis, electron microscopy, diffraction, and atom probe tomography. It is …
Influence Of The Inas Coverage On The Performance Of Submonolayer-Quantum-Dot Infrared Photodetectors Grown With A (2×4) Surface Reconstruction, Ahmad Alzeidan, Tiago F. De Cantalice, Kevin D. Vallejo, Paul J. Simmonds, Alain A. Quivy
Influence Of The Inas Coverage On The Performance Of Submonolayer-Quantum-Dot Infrared Photodetectors Grown With A (2×4) Surface Reconstruction, Ahmad Alzeidan, Tiago F. De Cantalice, Kevin D. Vallejo, Paul J. Simmonds, Alain A. Quivy
Materials Science and Engineering Faculty Publications and Presentations
Two infrared photodetectors based on submonolayer quantum dots, having a different InAs coverage of 35% and 50%, were grown, processed and tested. The detector with the larger coverage yielded a specific detectivity of 1.13×10 11 cm Hz 1/2 W -1 at 12K, which is among the highest values reported in the literature for that kind of device.