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High Precision In-Situ Raman Spectroscopy On A Novel Room-Temperature Superconductor, Carbonaceous Sulfur Hydride, Under Pressure And Cryogenic Temperatures, Faraz Mostafaeipour, Keith V. Lawler Ph.D., Ashkan Salamat Ph.D. Nov 2021

High Precision In-Situ Raman Spectroscopy On A Novel Room-Temperature Superconductor, Carbonaceous Sulfur Hydride, Under Pressure And Cryogenic Temperatures, Faraz Mostafaeipour, Keith V. Lawler Ph.D., Ashkan Salamat Ph.D.

Undergraduate Research Symposium Podium Presentations

Superconductivity is an incredible quantum phenomenon that historically only occurred at low temperatures. Recently, room-temperature superconductivity was discovered and will have various benefits and advantages in application, such as revolutionizing the energy grid, making medical imaging more accessible, and solving problems in related sciences. We have experimentally investigated carbonaceous sulfur hydride (CSH), a novel room-temperature superconductor, at varying cryogenic temperatures and pressures through high precision Raman spectroscopy. The current understanding of the material lacks information about the chemical structure and stoichiometry. Investigating the temperature and pressure space of its Raman spectra will give insight on important details about its structure, …

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Investigating The Growth Of Algae Under Low Atmospheric Pressures For Potential Food And Oxygen Production On Mars, Leena M. Cycil, Elisabeth M. Hausrath, Douglas W. Ming, Christopher T. Adcock, James Raymond, Daniel Remias, Warren P. Ruemmele Nov 2021

Investigating The Growth Of Algae Under Low Atmospheric Pressures For Potential Food And Oxygen Production On Mars, Leena M. Cycil, Elisabeth M. Hausrath, Douglas W. Ming, Christopher T. Adcock, James Raymond, Daniel Remias, Warren P. Ruemmele

Geoscience Faculty Research

With long-term missions to Mars and beyond that would not allow resupply, a self-sustaining Bioregenerative Life Support System (BLSS) is essential. Algae are promising candidates for BLSS due to their completely edible biomass, fast growth rates and ease of handling. Extremophilic algae such as snow algae and halophilic algae may also be especially suited for a BLSS because of their ability to grow under extreme conditions. However, as indicated from over 50 prior space studies examining algal growth, little is known about the growth of algae at close to Mars-relevant pressures. Here, we explored the potential for five algae species …

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The Real Me: Shared Technology’S Impact On Status From The Lens Of Positioning Theory, Christina Nishiyama, Michael E. Nussbaum, Michael S. Van Winkle Nov 2021

The Real Me: Shared Technology’S Impact On Status From The Lens Of Positioning Theory, Christina Nishiyama, Michael E. Nussbaum, Michael S. Van Winkle

College of Education Faculty Research

Participation in collaborative learning environments has demonstrated significant learning advantages due to opportunities for group members to contribute to shared problem-solving processes, shared goals, and co-elaboration of knowledge. Furthermore, research has shown that higher levels of social perceptiveness are positively correlated with higher levels of group performance. However, collaboration is not always successful, sometimes exhibiting imbalances of power and status. In this study, positioning theory and interaction analysis were used to investigate (a) interactions in four racially and gender-mixed groups (of three university students each) working with technology and (b) their negotiated positions of power and status. Results showed that …

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Communication Today: Were Watzlawick & Co. Wrong?, Dominik Godat, Elfie J. Czerny Nov 2021

Communication Today: Were Watzlawick & Co. Wrong?, Dominik Godat, Elfie J. Czerny

Journal of Solution Focused Practices

No abstract provided.

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Global 3d Radiation Hydrodynamic Simulations Of Proto-Jupiter’S Convective Envelope, Zhaohuan Zhu, Yan-Fei Jiang, Hans Baehr, Andrew N. Youdin, Philip J. Armitage, Rebecca G. Martin Nov 2021

Global 3d Radiation Hydrodynamic Simulations Of Proto-Jupiter’S Convective Envelope, Zhaohuan Zhu, Yan-Fei Jiang, Hans Baehr, Andrew N. Youdin, Philip J. Armitage, Rebecca G. Martin

Physics & Astronomy Faculty Research

The core accretion model of giant planet formation has been challenged by the discovery of recycling flows between the planetary envelope and the disc that can slow or stall envelope accretion. We carry out 3D radiation hydrodynamic simulations with an updated opacity compilation to model the proto-Jupiter’s envelope. To isolate the 3D effects of convection and recycling, we simulate both isolated spherical envelopes and envelopes embedded in discs. The envelopes are heated at given rates to achieve steady states, enabling comparisons with 1D models. We vary envelope properties to obtain both radiative and convective solutions. Using a passive scalar, we …

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Generating Synthetic Training Data For Deep Learning-Based Uav Trajectory Prediction, Brendan T. Morris, Stefan Becker, Ronny Hug, Wolfgang Huebner, Michael Arens Oct 2021

Generating Synthetic Training Data For Deep Learning-Based Uav Trajectory Prediction, Brendan T. Morris, Stefan Becker, Ronny Hug, Wolfgang Huebner, Michael Arens

Electrical & Computer Engineering Faculty Research

Deep learning-based models, such as recurrent neural networks (RNNs), have been applied to various sequence learning tasks with great success. Following this, these models are increasingly replacing classic approaches in object tracking applications for motion prediction. On the one hand, these models can capture complex object dynamics with less modeling required, but on the other hand, they depend on a large amount of training data for parameter tuning. Towards this end, we present an approach for generating synthetic trajectory data of unmanned-aerial-vehicles (UAVs) in image space. Since UAVs, or rather quadrotors are dynamical systems, they can not follow arbitrary trajectories. …

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Evolution Of Publications, Subjects, And Co-Authorships In Network-On-Chip Research From A Complex Network Perspective, Weilong Chen, Xiaohang Wang, Ye Sun, Qiao Hu, Letian Huang, Yingtao Jiang, Amit Kumar Singh, Terrence Mak, Mei Yang Oct 2021

Evolution Of Publications, Subjects, And Co-Authorships In Network-On-Chip Research From A Complex Network Perspective, Weilong Chen, Xiaohang Wang, Ye Sun, Qiao Hu, Letian Huang, Yingtao Jiang, Amit Kumar Singh, Terrence Mak, Mei Yang

College of Engineering Faculty Research

The academia and industry have been pursuing network-on-chip (NoC) related research since two decades ago when there was an urgency to respond to the scaling and technological challenges imposed on intra-chip communication in SoC designs. Like any other research topic, NoC inevitably goes through its life cycle: A. it started up (2000-2007) and quickly gained traction in its own right; B. it then entered the phase of growth and shakeout (2008-2013) with the research outcomes peaked in 2010 and remained high for another four/five years; C. NoC research was considered mature and stable (2014-2020), with signs showing a steady slowdown. …

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Multi-Messenger Astrophysics With Theseus In The 2030s, Bing Zhang, Numerous Authors, See Full List Below Oct 2021

Multi-Messenger Astrophysics With Theseus In The 2030s, Bing Zhang, Numerous Authors, See Full List Below

Physics & Astronomy Faculty Research

Multi-messenger astrophysics is becoming a major avenue to explore the Universe, with the potential to span a vast range of redshifts. The growing synergies between different probes is opening new frontiers, which promise profound insights into several aspects of fundamental physics and cosmology. In this context, THESEUS will play a central role during the 2030s in detecting and localizing the electromagnetic counterparts of gravitational wave and neutrino sources that the unprecedented sensitivity of next generation detectors will discover at much higher rates than the present. Here, we review the most important target signals from multi-messenger sources that THESEUS will be …

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Cognitive Effects Of The Bet Protein Inhibitor Apabetalone: A Prespecified Montreal Cognitive Assessment Analysis Nested In The Betonmace Randomized Controlled Trial, Jeffrey Cummings, Gregory G. Schwartz, Stephen J. Nicholls, Aziz Khan, Chris Halliday, Peter P. Toth, Michael Sweeney, Jan O. Johansson, Norman C.W. Wong, Ewelina Kulikowski, Kamyar Kalantar-Zadeh, Kenneth Lebioda, Henry N. Ginsberg, Bengt Winblad, Henrik Zetterberg, Kausik K. Ray Oct 2021

Cognitive Effects Of The Bet Protein Inhibitor Apabetalone: A Prespecified Montreal Cognitive Assessment Analysis Nested In The Betonmace Randomized Controlled Trial, Jeffrey Cummings, Gregory G. Schwartz, Stephen J. Nicholls, Aziz Khan, Chris Halliday, Peter P. Toth, Michael Sweeney, Jan O. Johansson, Norman C.W. Wong, Ewelina Kulikowski, Kamyar Kalantar-Zadeh, Kenneth Lebioda, Henry N. Ginsberg, Bengt Winblad, Henrik Zetterberg, Kausik K. Ray

School of Medicine Faculty Research

Background: Epigenetic changes may contribute importantly to cognitive decline in late life including Alzheimer's disease (AD) and vascular dementia (VaD). Bromodomain and extra-terminal (BET) proteins are epigenetic 'readers' that may distort normal gene expression and contribute to chronic disorders. Objective: To assess the effects of apabetalone, a small molecule BET protein inhibitor, on cognitive performance of patients 70 years or older participating in a randomized trial of patients at high risk for major cardiovascular events (MACE). Methods: The Montreal Cognitive Assessment (MoCA) was performed on all patients 70 years or older at the time of randomization. 464 participants were randomized …

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Initial Acoustoelastic Measurements In Olivine: Investigating The Effect Of Stress On P- And S-Wave Velocities, Taryn K. Traylor, Pamela C. Burnley, M. L. Whitaker Oct 2021

Initial Acoustoelastic Measurements In Olivine: Investigating The Effect Of Stress On P- And S-Wave Velocities, Taryn K. Traylor, Pamela C. Burnley, M. L. Whitaker

Geoscience Faculty Research

It is well known that elasticity is a key physical property in the determination of the structure and composition of the Earth and provides critical information for the interpretation of seismic data. This study investigates the stress-induced variation in elastic wave velocities, known as the acoustoelastic effect, in San Carlos olivine. A recently developed experimental ultrasonic acoustic system, the Directly Integrated Acoustic System Combined with Pressure Experiments (DIASCoPE), was used with the D-DIA multi-anvil apparatus to transmit ultrasonic sound waves and collect the reflections. We use the DIASCoPE to obtain longitudinal (P) and shear (S) elastic wave velocities from San …

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Thermal Analysis Of Benzotriazolium Perrhenate And Its Implication To Rhenium Metal, James Louis-Jean, Harry Jang, Andrew J. Swift, Frederic Poineau Sep 2021

Thermal Analysis Of Benzotriazolium Perrhenate And Its Implication To Rhenium Metal, James Louis-Jean, Harry Jang, Andrew J. Swift, Frederic Poineau

Chemistry and Biochemistry Faculty Research

The thermal analysis behavior of C6H6N3[ReO4] was studied by simultaneous thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC) up to 700 °C under argon. Such analysis afforded rhenium metal, which was characterized by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX) spectroscopy. XRD peak broadening due to crystallite size and lattice strain was analyzed by both Williamson-Hall (W-H) and Debye-Scherrer (D-S) methods. Efforts to isolate Re metal from the thermal treatment of benzotriazole (BTA = C6H5N3) with NH4ReO4 and Re2O7 under various atmospheres and temperatures are also reported. The results provide a significant insight into …

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Physical And Mental Disabilities Among The Gender-Diverse Population Using The Behavioral Risk Factor Surveillance System, Brfss (2017–2019): A Propensity-Matched Analysis, Jennifer R. Pharr, Kavita Batra Sep 2021

Physical And Mental Disabilities Among The Gender-Diverse Population Using The Behavioral Risk Factor Surveillance System, Brfss (2017–2019): A Propensity-Matched Analysis, Jennifer R. Pharr, Kavita Batra

Environmental & Global Health Faculty Research

This propensity-matched analysis utilized the publicly available Behavioral Risk Factor Surveillance System (2017–2019) data to compare the burden of disabilities among transgender/non-binary (TGNB) and cisgender groups. The groups were matched (1:1 ratio) on demographic variables using Nearest Neighborhood Matching. Categorical variables were compared among groups using a Chi-square analysis to test differences in the proportions. Multivariate logistic regression analysis was fit to predict the likelihood of the physical and mental disabilities among the TGNB group compared with the cisgender group while controlling for healthcare access factors, income, and employment. Survey weights were included in the model to account for the …

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Carbon Ion Radiotherapy In The Management Of Hepatocellular Carcinoma, Belal Abousaida, Danushka Seneviratne, Bradford S. Hoppe, Stephen J. Ko, Aroumougame Asaithamby, Francis A. Cucinotta, Jessica M. Kirwan, Kabir Mody, Beau Toskich, Jonathan B. Ashman, Christopher L. Hallemeier, Sunil Krishnan Sep 2021

Carbon Ion Radiotherapy In The Management Of Hepatocellular Carcinoma, Belal Abousaida, Danushka Seneviratne, Bradford S. Hoppe, Stephen J. Ko, Aroumougame Asaithamby, Francis A. Cucinotta, Jessica M. Kirwan, Kabir Mody, Beau Toskich, Jonathan B. Ashman, Christopher L. Hallemeier, Sunil Krishnan

Health Physics and Diagnostic Sciences Faculty Research

Localized hepatocellular carcinoma (HCC) that is unresectable and non-transplantable can be treated by several liver-directed therapies. External beam radiation therapy (EBRT) is an increasingly accepted and widely utilized treatment modality in this setting. Accelerated charged particles such as proton beam therapy (PBT) and carbon ion radiation therapy (CIRT) offer technological advancements over conventional photon radiotherapy. In this review, we summarize the distinct advantages of CIRT use for HCC treatment, focusing on physical and biological attributes, and outline dosimetric and treatment planning caveats. Based on these considerations, we posit that HCC may be among the best indications for use of CIRT, …

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Shallow Rupture Propagation Of Pleistocene Earthquakes Along The Hurricane Fault, Ut, Revealed By Hematite (U-Th)/He Thermochronometry And Textures, Madison P. Taylor, Alexis K. Ault, Margaret L. Odlum, Dennis L. Newell Sep 2021

Shallow Rupture Propagation Of Pleistocene Earthquakes Along The Hurricane Fault, Ut, Revealed By Hematite (U-Th)/He Thermochronometry And Textures, Madison P. Taylor, Alexis K. Ault, Margaret L. Odlum, Dennis L. Newell

Geoscience Faculty Research

The material properties and distribution of faults above the seismogenic zone promote or inhibit earthquake rupture propagation. We document the depths and mechanics of fault slip along the seismically active Hurricane fault, UT, with scanning and transmission electron microscopy and hematite (U-Th)/He thermochronometry. Hematite occurs as mm-scale, striated patches on a >10 m2 thin, mirror-like silica fault surface. Hematite textures include bulbous aggregates and cataclasite, overlain by crystalline Fe-oxide nanorods and an amorphous silica layer at the slip interface. Textures reflect mechanical, fluid, and heat-assisted amorphization of hematite and silica-rich host rock that weaken the fault and promote rupture propagation. …

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Novel Theorems And Algorithms Relating To The Collatz Conjecture, Michael R. Schwob, Peter Shiue, Rama Venkat Sep 2021

Novel Theorems And Algorithms Relating To The Collatz Conjecture, Michael R. Schwob, Peter Shiue, Rama Venkat

Mathematical Sciences Faculty Research

Proposed in 1937, the Collatz conjecture has remained in the spotlight for mathematicians and computer scientists alike due to its simple proposal, yet intractable proof. In this paper, we propose several novel theorems, corollaries, and algorithms that explore relationships and properties between the natural numbers, their peak values, and the conjecture. These contributions primarily analyze the number of Collatz iterations it takes for a given integer to reach 1 or a number less than itself, or the relationship between a starting number and its peak value.

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Gw Ori: Circumtriple Rings And Planets, Jeremy L. Smallwood, Rebecca Nealon, Cheng Chen, Rebecca G. Martin, Jiaqing Bi, Ruobing Dong, Christophe Pinte Sep 2021

Gw Ori: Circumtriple Rings And Planets, Jeremy L. Smallwood, Rebecca Nealon, Cheng Chen, Rebecca G. Martin, Jiaqing Bi, Ruobing Dong, Christophe Pinte

Physics & Astronomy Faculty Research

GW Ori is a hierarchical triple star system with a misaligned circumtriple protoplanetary disc. Recent Atacama Large Millimeter/submillimeter Array observations have identified three dust rings with a prominent gap at 100 au and misalignments between each of the rings. A break in the gas disc may be driven by the torque from either the triple star system or a planet that is massive enough to carve a gap in the disc. Once the disc is broken, the rings nodally precess on different time-scales and become misaligned. We investigate the origins of the dust rings by means of N-body integrations and …

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Inelastic, Exchange, And Reactive Processes In Rovibrationally Excited Collisions Of Hd With H, Boyi Zhou, Benhui Yang, Balakrishnan Naduvalath, B. K. Kendrick, Maodu Chen, P. C. Stancil Sep 2021

Inelastic, Exchange, And Reactive Processes In Rovibrationally Excited Collisions Of Hd With H, Boyi Zhou, Benhui Yang, Balakrishnan Naduvalath, B. K. Kendrick, Maodu Chen, P. C. Stancil

Chemistry and Biochemistry Faculty Research

The HD molecule is an important coolant in early universe chemistry models and a tracer of H2 in star-forming regions. Rate coefficients for collisional excitation and de-excitation of HD rotational and vibrational levels form important ingredients in astrophysical models. While collisions with He, H2, and H are the most important, available data for H + HD collisions are largely limited to temperatures less than 1000 K for the vibrational ground state, low-lying rotational levels of the v = 1 HD vibrational level, or computed without reactive contributions. Here, through explicit quantum scattering calculations, we report extensive data for rovibrational transitions …

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On The Solutions Of Three-Variable Frobenius-Related Problems Using Order Reduction Approach, Tian-Xiao He, Peter J.-S. Shiue, Rama Venkat Sep 2021

On The Solutions Of Three-Variable Frobenius-Related Problems Using Order Reduction Approach, Tian-Xiao He, Peter J.-S. Shiue, Rama Venkat

Mathematical Sciences Faculty Research

This paper presents a new approach to determine the number of solutions of three-variable Frobenius-related problems and to find their solutions by using order reducing methods. Here, the order of a Frobenius-related problem means the number of variables appearing in the problem. We present two types of order reduction methods that can be applied to the problem of finding all nonnegative solutions of three-variable Frobenius-related problems. The first method is used to reduce the equation of order three from a three-variable Frobenius-related problem to be a system of equations with two fixed variables. The second method reduces the equation of …

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The Onset Of Exercise-Associated Hyponatremia And Individual Differences In Inappropriate Arginine Vasopressin Excretion: A Review Of Proposed Mechanisms, Michelle Stehman, Stephen A. Maris Sep 2021

The Onset Of Exercise-Associated Hyponatremia And Individual Differences In Inappropriate Arginine Vasopressin Excretion: A Review Of Proposed Mechanisms, Michelle Stehman, Stephen A. Maris

Topics in Exercise Science and Kinesiology

Topics in Exercise Science and Kinesiology Volume 2: Issue 1, Article 10, 2021. Exercise-associated hyponatremia (EAH) has been reported to develop during endurance events such as triathlons and marathons. As these events become more popular, the incidence of developing EAH also increases. The development of EAH is commonly associated with the overconsumption of hypotonic fluids such as water and tends to be more prevalent in females. There is also evidence to suggest the inappropriate secretion of arginine vasopressin (AVP) leading to water retention may predispose an individual for developing EAH, especially when coupled with the overconsumption of fluids. Recent research …

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Direct H-He Chemical Association In Superionic Feo2H2He At Deep-Earth Conditions, Jurong Zhang, Hanyu Liu, Yanming Ma, Changfeng Chen Sep 2021

Direct H-He Chemical Association In Superionic Feo2H2He At Deep-Earth Conditions, Jurong Zhang, Hanyu Liu, Yanming Ma, Changfeng Chen

Physics & Astronomy Faculty Research

Hydrogen and helium are known to play crucial roles in geological and astrophysical environments; however, they are inert toward each other across wide pressure-temperature (P-T) conditions. Given their prominent presence and influence on the formation and evolution of celestial bodies, it is of fundamental interest to explore the nature of interactions between hydrogen and helium. Using an advanced crystal structure search method, we have identified a quaternary compound FeO2H2He stabilized in a wide range of P-T conditions. Ab initio molecular dynamics simulations further reveal a novel superionic state of FeO2H2He hosting liquid-like …

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The House Edge And Play Time: Do Industry Heuristics Fairly Describe This Relationship?, Anthony F. Lucas, A.K. Singh Sep 2021

The House Edge And Play Time: Do Industry Heuristics Fairly Describe This Relationship?, Anthony F. Lucas, A.K. Singh

UNLV Gaming Research & Review Journal

Based on modified versions of licensed pay tables from reel slot machines, simulations of play failed to indicate a statistically significant difference in the spins per losing player (SPLP), despite a marked difference in the pars (i.e., 7.9% vs. 12.9%). To reflect a volume of play consistent with frequent gambling, the simulations included results from 1-4 visits per week, for the equivalent of one year. Additionally, this level of play was repeated for 100 “years,” within multiple scenarios of buy-in amounts and stoppage-of-play criteria. Still, most outcomes indicated a negligible decline in SPLP, in spite of the 63%-increase in the …

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Transcontinental Retroarc Sediment Routing Controlled By Subduction Geometry And Climate Change (Central And Southern Andes, Argentina), Eduardo Garzanti, Tomas Capaldi, Giovanni Vezzoli, Mara Limonta, Numa Sosa Sep 2021

Transcontinental Retroarc Sediment Routing Controlled By Subduction Geometry And Climate Change (Central And Southern Andes, Argentina), Eduardo Garzanti, Tomas Capaldi, Giovanni Vezzoli, Mara Limonta, Numa Sosa

Geoscience Faculty Research

Central Argentina from the Pampean flat-slab segment to northern Patagonia (27°–41°S) represents a classic example of a broken retroarc basin with strong tectonic and climatic control on fluvial sediment transport. Combined with previous research focused on coastal sediments, this actualistic provenance study uses framework petrography and heavy-mineral data to trace multistep dispersal of volcaniclastic detritus first eastwards across central Argentina for up to ca. 1,500 km and next northwards for another 760 km along the Atlantic coast. Although detritus generated in the Andes is largely derived from mesosilicic volcanic rocks of the cordillera, its compositional signatures reflect different tectono-stratigraphic levels …

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A Mixed-Methods Analysis Of Educational Spaces And Black Identity Development, Kala Burrell-Craft, Danielle R. Eugene Aug 2021

A Mixed-Methods Analysis Of Educational Spaces And Black Identity Development, Kala Burrell-Craft, Danielle R. Eugene

Taboo: The Journal of Culture and Education

Guided by Critical Race Theory, Racial Space Theory, and Black Identity Development through the lens of the Nigrescence model, this mixed-methods study explored the links between educational spaces/places and Black identity development in a sample of Black professional adults (n=39). Correlation analysis revealed a weak positive relationship between space and Black racial identity and little to no correlational effect between place and Black racial identity. Three themes were identified: educational spaces, HBCU versus PWI debate, and stages of Black identity development with each providing more depth of understanding of how educational spaces influence Black identity development. Study implications are discussed.

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Vacancy Control In Acene Blends Links Exothermic Singlet Fission To Coherence, Clemens Zeiser, Chad Cruz, David R. Reichman, Michael Seitz, Jan Hagenlocher, Eric L. Chronister, Christopher J. Bardeen, Roel Tempelaar, Katharina Broch Aug 2021

Vacancy Control In Acene Blends Links Exothermic Singlet Fission To Coherence, Clemens Zeiser, Chad Cruz, David R. Reichman, Michael Seitz, Jan Hagenlocher, Eric L. Chronister, Christopher J. Bardeen, Roel Tempelaar, Katharina Broch

Chemistry and Biochemistry Faculty Research

The fission of singlet excitons into triplet pairs in organic materials holds great technological promise, but the rational application of this phenomenon is hampered by a lack of understanding of its complex photophysics. Here, we use the controlled introduction of vacancies by means of spacer molecules in tetracene and pentacene thin films as a tuning parameter complementing experimental observables to identify the operating principles of different singlet fission pathways. Time-resolved spectroscopic measurements in combination with microscopic modelling enables us to demonstrate distinct scenarios, resulting from different singlet-to-triplet pair energy alignments. For pentacene, where fission is exothermic, coherent mixing between the …

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Singlet Fission In Acene Blends, Katharina Broch, Clemens Zeiser, Chad Cruz, Luca Moretti, Margherita Maiuri, Eric Chronister, David Reichman, Roel Tempelaar, Giulio Cerullo, Christopher Bardeen Aug 2021

Singlet Fission In Acene Blends, Katharina Broch, Clemens Zeiser, Chad Cruz, Luca Moretti, Margherita Maiuri, Eric Chronister, David Reichman, Roel Tempelaar, Giulio Cerullo, Christopher Bardeen

Chemistry and Biochemistry Faculty Research

Singlet fission (SF), the photophysical process converting an excited singlet exciton into two triplet excitons, is a promising approach to boost solar cell efficiencies. It is controlled by various parameters such as intermolecular interactions, energetics, entropy and vibronic coupling and a controlled modification of these parameters is key to a fundamental understanding. Blends of organic semiconductors present an interesting alternative to established methods of chemical functionalization and their potential for the study of SF pathways will be discussed using acene blends as example. Mixed thin films of SF chromophores and weakly interacting, high-bandgap spacer molecules allow one to study the …

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Controllable Co2 Electrocatalytic Reduction Via Ferroelectric Switching On Single Atom Anchored In2se3 Monolayer, Lin Ju, Xin Tan, Xin Mao, Yuantong Gu, Sean Smith, Aijun Du, Zhongfang Chen, Changfeng Chen, Liangzhi Kou Aug 2021

Controllable Co2 Electrocatalytic Reduction Via Ferroelectric Switching On Single Atom Anchored In2se3 Monolayer, Lin Ju, Xin Tan, Xin Mao, Yuantong Gu, Sean Smith, Aijun Du, Zhongfang Chen, Changfeng Chen, Liangzhi Kou

Physics & Astronomy Faculty Research

Efficient and selective CO2 electroreduction into chemical fuels promises to alleviate environmental pollution and energy crisis, but it relies on catalysts with controllable product selectivity and reaction path. Here, by means of first-principles calculations, we identify six ferroelectric catalysts comprising transition-metal atoms anchored on In2Se3 monolayer, whose catalytic performance can be controlled by ferroelectric switching based on adjusted d-band center and occupation of supported metal atoms. The polarization dependent activation allows effective control of the limiting potential of CO2 reduction on TM@In2Se3 (TM = Ni, Pd, Rh, Nb, and Re) as well as the reaction paths and final products on …

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Terrestrial Planet Formation In A Circumbinary Disc Around A Coplanar Binary, Anna C. Childs, Rebecca G. Martin Aug 2021

Terrestrial Planet Formation In A Circumbinary Disc Around A Coplanar Binary, Anna C. Childs, Rebecca G. Martin

Physics & Astronomy Faculty Research

With N-body simulations, we model terrestrial circumbinary planet (CBP) formation with an initial surface density profile motivated by hydrodynamic circumbinary gas disc simulations. The binary plays an important role in shaping the initial distribution of bodies. After the gas disc has dissipated, the torque from the binary speeds up the planet formation process by promoting body-body interactions but also drives the ejection of planet building material from the system at an early time. Fewer but more massive planets form around a close binary compared to a single star system. A sufficiently wide or eccentric binary can prohibit terrestrial planet formation. …

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The Large Area Burst Polarimeter (Leap) A Nasa Mission Of Opportunity For The Iss, Bing Zhang, Numerous Authors, See Full List Below Aug 2021

The Large Area Burst Polarimeter (Leap) A Nasa Mission Of Opportunity For The Iss, Bing Zhang, Numerous Authors, See Full List Below

Physics & Astronomy Faculty Research

The LargE Area Burst Polarimeter (LEAP) will radically improve our understanding of some of the most energetic phenomena in our Universe by exposing the underlying physics that governs astrophysical jets and the extreme environment surrounding newborn compact objects. LEAP will do this by making the highest fidelity polarization measurements to date of the prompt gamma-ray emission from a large sample of Gamma-Ray Bursts (GRBs). The science objectives are met with a single instrument deployed as an external payload on the ISS-a wide FOV Compton polarimeter that measures GRB polarization from 50-500 keV and GRB spectra from ∼10 keV to 5 …

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Software For The Frontiers Of Quantum Chemistry: An Overview Of Developments In The Q-Chem 5 Package, Evgeny Epifanovsky, Andrew T.B. Gilbert, Xintian Feng, Joonho Lee, Yuezhi Mao, Narbe Mardirossian, Pavel Pokhilko, Alec F. White, Marc P. Coons, Adiran L. Dempwolff, Zhengting Gan, Diptarka Hait, Paul R. Horn, Leif D. Jacobson, Ilya Kaliman, Jorg Kussmann, Adrian W. Lange, Ka Un Lao, Daniel S. Levine, Jie Liu, Simon C. Mckenzie, Adrian F. Morrison, Kaushik D. Nanda, Felix Plasser, Dirk R. Rehn, Marta L. Vidal, Zhi-Qiang You, Ying Zhu, Bushra Alam, Benjamin J. Albrecht, Abdulrahman Aldossary Aug 2021

Software For The Frontiers Of Quantum Chemistry: An Overview Of Developments In The Q-Chem 5 Package, Evgeny Epifanovsky, Andrew T.B. Gilbert, Xintian Feng, Joonho Lee, Yuezhi Mao, Narbe Mardirossian, Pavel Pokhilko, Alec F. White, Marc P. Coons, Adiran L. Dempwolff, Zhengting Gan, Diptarka Hait, Paul R. Horn, Leif D. Jacobson, Ilya Kaliman, Jorg Kussmann, Adrian W. Lange, Ka Un Lao, Daniel S. Levine, Jie Liu, Simon C. Mckenzie, Adrian F. Morrison, Kaushik D. Nanda, Felix Plasser, Dirk R. Rehn, Marta L. Vidal, Zhi-Qiang You, Ying Zhu, Bushra Alam, Benjamin J. Albrecht, Abdulrahman Aldossary

Chemistry and Biochemistry Faculty Research

This article summarizes technical advances contained in the fifth major release of the Q-Chem quantum chemistry program package, covering developments since 2015. A comprehensive library of exchange–correlation functionals, along with a suite of correlated many-body methods, continues to be a hallmark of the Q-Chem software. The many-body methods include novel variants of both coupled-cluster and configuration-interaction approaches along with methods based on the algebraic diagrammatic construction and variational reduced density-matrix methods. Methods highlighted in Q-Chem 5 include a suite of tools for modeling core-level spectroscopy, methods for describing metastable resonances, methods for computing vibronic spectra, the nuclear–electronic orbital method, and …

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Dicationic Stilbazolium Salts: Structural, Thermal, Optical, And Ionic Conduction Properties, Pradip K. Bhowmik, Jung J. Koh, David King, Haesook Han, Benoît Heinrich, Bertrand Donnio, Daniel Zaton, Alfonso Martinez-Felipe Aug 2021

Dicationic Stilbazolium Salts: Structural, Thermal, Optical, And Ionic Conduction Properties, Pradip K. Bhowmik, Jung J. Koh, David King, Haesook Han, Benoît Heinrich, Bertrand Donnio, Daniel Zaton, Alfonso Martinez-Felipe

Chemistry and Biochemistry Faculty Research

Two series of new dicationic stilbazolium salts containing tosylate and triflimide counterions, respectively, were synthesized and characterized by spectroscopic techniques and elemental analysis. Despite of their promesogenic structures, none of these salts are mesomorphous, and instead they solely exhibit crystalline polymorphism, as deduced from differential scanning calorimetry, polarizing optical microscopy and variable temperature X-ray measurements. These salts were also found to be highly thermally stable with decomposition temperatures occurring well above 300 °C, and up to 367 °C for the triflimide salts, as determined by thermogravimetric analysis. UV–Vis absorption and photoluminescent properties were examined in both solution and in the …

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