Physical Sciences and Mathematics Commons^™

Data From: Two Names Of Stability: Spherical Aromatic Or Superatomic Intermetalloid Cluster [Pd3sn8bi6]4−, Alexander I. Boldyrev, Nikita Fedik

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Project reports the aromaticity in the intermetalloid cluster [Pd3Sn8Bi6]4−.

Data From: Stability, Electronic, And Optical Properties Of Two-Dimensional Phosphoborane, Alexander I. Boldyrev, Nikolay Tkachenko

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The structure and properties of two-dimensional phosphoborane sheets were computationally investigated using Density Functional Theory calculations. The calculated phonon spectrum and band structure point to dynamic stability and allowed characterization of the predicted two-dimensional material as a direct-gap semiconductor with a band gap of ~1.5 eV. The calculation of the optical properties showed that the two-dimensional material has a relatively small absorptivity coefficient. The parameters of the mechanical properties characterize the two-dimensional phosphoborane as a relatively soft material, similar to the monolayer of MoS2. Assessment of thermal stability by the method of molecular dynamics indicates sufficient stability of the predicted …

Data From: Novel Strongly Correlated Europium Superhydrides, Alexander I. Boldyrev, Nikolay Tkachenko

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We conducted a joint experimental–theoretical investigation of the high-pressure chemistry of europium polyhydrides at pressures of 86–130 GPa. We discovered several novel magnetic Eu superhydrides stabilized by anharmonic effects: cubic EuH9, hexagonal EuH9, and an unexpected cubic (Pm3n) clathrate phase, Eu8H46. Monte Carlo simulations indicate that cubic EuH9 has antiferromagnetic ordering with TN of up to 24 K, whereas hexagonal EuH9 and Pm3n-Eu8H46 possess ferromagnetic ordering with TC = 137 and 336 K, respectively. The electron–phonon interaction is weak in all studied europium hydrides, and their magnetic ordering excludes s-wave superconductivity, except, perhaps, for distorted pseudohexagonal EuH9. The equations of …

Data From: A Sandwich-Type Cluster Containing Ge@Pd3 Planar Fragment Flanked By Aromatic Nonagermanide Caps, Alexander I. Boldyrev, Nikolay Tkachenko

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Sandwich-type clusters with the planar fragment containing a heterometallic sheet have remained elusive. In this work, we introduce the [K(2,2,2-crypt)]4{(Ge9)2[η6-Ge(PdPPh3)3]} complex that contains a heterometallic sandwich fragment. The title compound is structurally characterized by means of single-crystal X-ray diffraction, which reveals the presence of an unusual heteroatomic metal planar fragment Ge@Pd3. The planar fragment contains a rare formal zerovalent germanium core and a peculiar bonding mode of sp2-Ge@(PdPPh3)3 trigonal planar structure, whereas the nonagermanide fragments act as capping ligands. The chemical bonding pattern of the planar fragment consists of three 2c-2e Pd-Ge σ-bonds attaching Pd atoms to the core Ge …

Data From: Chemical Bonding Analysis Of Excited States Using The Adaptive Natural Density Partitioning Method, Alexander I. Boldyrev, Nikolay Tkachenko

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A novel approach to chemical bond analysis for excited states has been developed. Using an extended adaptive natural density partitioning method (AdNDP) as implemented in AdNDP 2.0 code, we obtained chemically intuitive bonding patterns for the excited states of H2O, B5+, and C2H4+ molecules. The deformation pathway in the excited states could be easily predicted based on the analysis of the chemical bond pattern. We expect that this new method of chemical bonding analysis would be very helpful for photochemistry, photoelectron spectroscopy, electron spectroscopy and other chemical applications that involved excited states.

Dataset For: Multiple Local Σ-Aromaticity Of Nonagermanide Clusters, Alexander I. Boldyrev, Nikolay Tkachenko

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Nonagermanide clusters are widely used in inorganic synthesis and are actively studied by experimentalists and theoreticians. However, chemical bonding of such versatile species is still not completely understood. In our work we deciphered a bonding pattern for various experimentally obtained nonagermanide species. We localized the electron density via the AdNDP algorithm for the model structures ([Ge9]4−, [Ge9{P(NH2)2}3]−, Cu[Ge9{P(NH2)2}3] and Cu(NHC)[Ge9{P(NH2)2}3]) and obtained a simple and chemically intuitive bonding pattern which can explain the variety of active sites and the existence of both D3h and C4v geometries for such clusters. Moreover, the [Ge9]4− core is found to be a unique example …

Data From: Computational Prediction Of The Low-Temperature Ferromagnetic Semiconducting 2d Sin Monolayer, Alexander I. Boldyrev, Nikolay Tkachenko

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Since the discovery of graphene, 2D materials have captured the minds of scientists because of their attractive and unique electronic properties. In particular, magnetic 2D materials have become a subject of extensive discussions today. Using density functional theory calculations, it is shown that 2D SiN sheet (built out of nonmetallic main group atoms) is a ferromagnetic semiconducting material with a magnetic moment 1 μB per unit cell and an indirect bandgap of 1.55 eV. Calculated phonon spectrum and conducted ab initio molecular dynamics simulation reveal thermal and dynamical stability of the designed material. It is shown that the ferromagnetic state …

Data From: Dibridged, Monobridged, Vinylidene-Like, And Linear Structures For The Alkaline Earth Dihydrides Be2h2, Mg2h2, Ca2h2, Sr2h2, And Ba2h2. Proposals For Observations, Alexander I. Boldyrev, Nikolay Tkachenko

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This research reports a search for peculiar monobridged structures of the E2H2 molecules (E = Be, Mg, Ca, Sr, Ba). For Be2H2 and Mg2H2, the monobridged geometry is not an equilibrium but rather a transition state between the vinylidene-like structure and the global minimum HE–EH linear geometry. However, for Ca2H2, Sr2H2, and Ba2H2, this situation changes significantly; the linear structure is no longer the global minimum but lies higher in energy than two other equilibria, the dibridged and monobridged structures. The planar dibridged structures of both Sr2H2 and Ba2H2 should be observable via IR spectroscopy. Although the remarkable monobridged structures …

Data For: Record Low Ionization Potentials Of Alkali Metal Complexes With Crown Ethers And Cryptands, Alexander I. Boldyrev, Nikolay Tkachenko

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Electronic properties of series of alkali metals complexes with crown ethers and cryptands were studied via DFT hybrid functionals. For [M([2.2.2]crypt)] (M=Li, Na, K) extremely low (1.70–1.52 eV) adiabatic ionization potentials were found. Such low values of ionization energies are significantly lower than those of alkali metal atoms. Thus, the investigated complexes can be defined as superalkalis. As a result, our investigation opens up new directions in the designing of chemical species with record low ionization potentials and extends the explanation of the ability of the cryptates and alkali crown ether complexes to stabilize multiple charged Zintl ions.

Data From: Structure And Bonding In [Sb@In8sb12]3− And [Sb@In8sb12]5−, Alexander I. Boldyrev, Nikolay Tkachenko

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We report the characterization of the compound [K([2.2.2]crypt)]4[In8Sb13], which proves to contain a 1:1 mixture of [Sb@In8Sb12]3− and [Sb@In8Sb12]5−. The tri-anion displays perfect Th symmetry, the first completely inorganic molecule to do so, and contains eight equivalent In3+ centers in a cube. The gas-phase potential energy surface of the penta-anion has eight equivalent minima where the extra pair of electrons is localized on one In+ center, and these minima are linked by low-lying transition states where the electron pair is delocalized over two adjacent centers. The best fit to the electron density is obtained from a model where the structure …

Data From: Σ-Aromaticity-Induced Stabilization Of Heterometallic Supertetrahedral Clusters [Zn6ge16]4− And [Cd6ge16]4−, Alexander I. Boldyrev, Nikolay Tkachenko

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In this work, the largest heterometallic supertetrahedral clusters, [Zn6Ge16]4− and [Cd6Ge16]4−, were directly self-assembled through highly-charged [Ge4]4− units and transition metal cations, in which 3-center–2-electron σ bonding in Ge2Zn or Ge2Cd triangles plays a vital role in the stabilization of the whole structure. The cluster structures have an open framework with a large central cavity of diameter 4.6 Å for Zn and 5.0 Å for Cd, respectively. Time-dependent HRESI-MS spectra show that the larger clusters grow from smaller components with a single [Ge4]4− and ZnMes2 units. Calculations performed at the DFT level indicate a very large HOMO–LUMO energy gap in …

Data From: All-Metal Σ-Antiaromaticity In Dimeric Cluster Anion {[Cuge9mes]2}4−, Alexander I. Boldyrev, Nikolay Tkachenko

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In this work, we report a dimeric cluster anion, {[CuGe9Mes]2}4−, which was isolated as the [K(2,2,2-crypt)]+ salt and characterized by using single-crystal X-ray diffraction and ESI mass spectroscopy. The title cluster represents the first locally σ-antiaromatic compound in the solid state, as well as the first heteroatomic antiaromatic compound.

Digital Appendix Of Masters Thesis "Constraining Deformation Mechanisms Of Damage Zones: A Case Study Of The Shallow San Andreas Fault At Elizabeth Lake, Southern California, James P. Evans, Caroline Studnicky

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We performed macroscopic, optical petrographic, scanning electron microscopy, and geochemical analyses on rock core acquired across the San Andreas Fault at Elizabeth Lake, California, in order to understand the distribution and accommodation of fault-related slip and energy within the shallow damage zone of this continental scale strike-slip fault. We characterized the deformation structures, alteration textures, and elemental variabilities to constrain the properties of the uppermost ~2 km fault-related damage zone at this site. We identified evidence for coseismic slip in the form of pulverized rocks, injection veins, clay-clast aggregates, and pseudotachylyte, and aseismic slip through calcite twins, dilatant vein fills, …

Standard Non-Uniform Noise Dataset, Andres Imperial, John M. Edwards

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Fixed Pattern Noise Non-Uniformity Correction through K-Means Clustering

Fixed pattern noise removal from imagery by software correction is a practical approach compared to a physical hardware correction because it allows for correction post-capture of the imagery. Fixed pattern noise presents a unique challenge for de-noising techniques as the noise does not present itself where large number statistics are effective. Traditional noise removal techniques such as blurring or despeckling produce poor correction results because of a lack of noise identification. Other correction methods developed for fixed pattern noise can often present another problem of misidentification of noise. This problem can result …

Data On The Effects Of Persuasive Message Content On Retweet Counts During Natural Hazard Events, Yajie Li, Amanda L. Hughes, Peter D. Howe

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This dataset contains Twitter messages about heat hazards posted by U.S. National Weather Service accounts in 2016. The dataset also contains the retweet counts of the heat-related tweets and whether several types of persuasive message content were included in each tweet. The population and temperature for the forecast area of each sending National Weather Service account are also included.

Na Lidar And Mighti/Icon Investigation On Turbopause Tidal Waves, Tao Yuan, Michael H. Stevens, Christoph R. Englert, Thomas J. Immel

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Local full diurnal coverage of temperature variations across the turbopause (~ 90 km to 115 km altitude) is achieved by combining the nocturnal observations of a Sodium (Na) Doppler lidar on the Utah State University (USU) campus (41.7?N, 248.2?E) and NASA MIGHTI/ICON daytime observations made in the same vicinity. In this paper, utilizing this hybrid dataset during summer 2020 between June 12th and July 15th, we retrieve the temperature signatures of diurnal and semidiurnal tidal waves in this region. The tidal amplitudes are similar for both components: less than 5 K below ~ 98 km but increase considerably above, up …

Data From: Realization Of Lewis Basic Sodium Anion In The Nabh3- Cluster, Alexander I. Boldyrev, Nikita Fedik

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Project reports the first example of dative bond formed by Na- (anion) in a cluster NaBH3-.

Data For "Arch_Covid_Crowding_Vc", Wayne Freimund, Zachary D. Miller

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Monitoring of visitor use in Arches National Park to assess social distancing behaviors of visitors during the COVID-19 pandemic.

Data From: Anomalous Electron Temperature, Bela G. Fejer

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Anomalous Electron Temperatures in the evening equatorial ionosphere. These are outputs of simulations from the semi-empirical SAMI2-PE (Varney et al. 2012) for the night of the 02 and 05 August 2011.

Genetic Variation At The Species And Population Levels In The Rocky Mountain Ridged Mussel (Gonidea Angulata) – Supplementary Material, James A. Walton, Karen E. Mock, Steven F. R. Brownlee, Jon H. Mageroy, Greg Wilson, Ian R. Walker

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Freshwater mussels in western North America are threatened by water diversions, climate change, loss of required host fish, and other factors, and have experienced marked decline in the past several decades. All four of the primary lineages (potentially species) of freshwater mussels in the western U.S. and Canada are widespread and have somewhat generalist host fish requirements. Of these lineages, perhaps the most poorly understood and of greatest conservation concern is Gonidea angulata (Rocky Mountain ridged mussel). Gonidea is a monotypic genus occurring only in the western continental U.S. and southern Canada. Here we describe the patterns of genetic variation …

Tdim Ionospheric Model Tec, Hmf2, And Nmf2 At Mid-Latitude Northern Hemisphere, Used In The Paper Titled "Is Tec A Viable Servo Input?", Jan J. Sojka

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The externally imposed vertical drift in the F region is an extremely important driver of ionospheric dynamics but is very difficult to measure or map. Ionospheric servo algorithms have used hmF2 as F-region observable to infer the vertical drift. However, an even more plentiful observable is the total electron content (TEC) whose coverage over northern mid-latitudes has both spatial and temporal availability that matches those of the probable mechanisms responsible for vertical drift dynamics.

This ionospheric, first principle physics, study shows that TEC is a viable servo parameter at mid-latitudes in the noon sector. The servo relationship is shown to …

Technology Belmont Data, Christopher Monz, Vera Hausner, Jennifer Schmidt

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The data is based on semi-structured household interviews conducted in Noatak (n = 12), Noorvik (n = 11), and Brevig Mission (n = 12) in the March of 2017. Information gathered consists of individuals use of technology, perceptions about how technology has helped or hindered their ability to do subsistence and address the changing climate, and the role of technology in the community. Demographic information includes gender, race, education, household size, and employment status. Individuals who were particularly knowledgeable and amendable participated in a q-sort exercise to assess values and beliefs regarding technology in their community. Individual records are confidential …

Determining How Increasing Precipitation Intensity Will Impact Rangelands In Utah., Karen H. Beard, Andrew Kulmatiski

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As the atmosphere warms, precipitation events become larger, but less frequent. Yet, there is fundamental disagreement about how increased precipitation intensity will affect vegetation. Walter’s two-layer hypothesis and experiments testing it have demonstrated that precipitation intensity can increase woody plant growth. Observational studies have found the opposite pattern. Not only are the patterns contradictory, but inference is largely limited to grasslands and savannas. We tested the effects of increased precipitation intensity in a shrub-steppe ecosystem that receives >30% of its precipitation as snow. We used 11 (8 m x 8 m) shelters to collect and redeposit rain and snow as …

Coqui Frog Predator Avoidance And Recognition, Karen H. Beard

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The purpose of this study was to determine whether coqui frogs from their non-native range responded to native predators the same way as frogs from their native range. Frogs were collected from two sites in Puerto Rico (El Yunque and Rio Abajo) in May 2006 and one site in Hawaii (Hilo) in June 2006. At each site, frogs were collected from a high (> 700 m) and low (< 300 m) elevation population. Of the total number of frogs collected, 100 males were randomly selected to be used in this study (45 and 55 from Hawaii and Puerto Rico, respectively). Three tailless whipscorpions (Phrynus longipes) and three tarantulas (Avicularia laeta) were also collected in Puerto Rico in field sites where frogs were collected and shipped back to a laboratory.

Development Of A Low-Cost, Open Source Miniature Rotary Cell Culture System To Simulate Microgravity Within An Irradiated Environment, Elizabeth Vargis, Jr Dennison

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A major challenge for astronauts in long-duration space travel is combatting the hazardous spaceflight environment caused by microgravity and increased levels of ionizing radiation. Microgravity damages cellular DNA by increasing the production of harmful reactive oxygen species, while ionizing radiation damages DNA by creating double-stranded DNA (dsDNA) breaks. Cellular damage due to microgravity and radiation has been investigated using ground-based models, but most models consider microgravity and ionizing radiation alone, or asynchronously. Synchronous modeling better mimics spaceflight conditions and can be used to understand the combined effects of microgravity and ionizing radiation. However, commercially available devices to model microgravity and …

Supplemental Material For Cotterill Et Al. 2020: Parsing The Effects Of Demography, Climate, And Management On Recurrent Brucellosis Outbreaks In Elk. Journal Of Applied Ecology., Gavin G. Coterill, Johan T. Du Toit, Paul C. Cross

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Zoonotic pathogens can harm human health and wellbeing directly or by impacting livestock. Pathogens that spillover from wildlife can also impair conservation efforts if humans perceive wildlife as pests. Brucellosis, caused by the bacterium Brucella abortus, circulates in elk and bison herds of the Greater Yellowstone Ecosystem and poses a risk to cattle and humans. Our goal was to understand the relative effects of climatic drivers, host demography, and management control programs on disease dynamics.

Synthesis and applications: Positive serostatus is often weakly correlated with infectiousness but is nevertheless used to make management decisions including lethal removal in wildlife disease …

Meps Data Assimilation System, Robert W. Schunk, Larry Gardner

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For the current funding opportunity we propose to develop a master system that will enhance the user interface to the MEPS model and enable the scientific community to efficiently use the model. Furthermore, we will build and automate validation tools and improve the efficiency and robustness of the MEPS ensemble averaging scheme. Finally, we will explore the nest step toward a major advancement in MEPS b significantly improving the spatial resolution of one of the data assimilation models to explore meso- and small-scale features.

Isotope Summary Data, Andrew Kulmatiski

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Data includes deuterium tracer uptake data from plant species at the US Sheep Experiment Station.

Aluminum Secondary Electron Yield, Jr Dennison, Phillip Lundgreen

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Accurate modeling of spacecraft charging is essential to mitigate well-known and all-too-common deleterious and costly effects on spacecraft resulting from charging induced by interactions with the space plasma environment. This paper addresses how limited availability of electron emission and transport properties of spacecraft materials—in particular secondary electron yields—and the wide range measured for such properties pose a critical issue for modeling spacecraft charging. It describes a materials charging database being developed, which when used in concert with the strategies outlined herein for best practices for establishing optimized materials properties for spacecraft charging models and specific mission requirements and how these …

Data From: Cavitation Clusters In Lipid Systems – The Generation Of A Bifurcated Streamer And The Dual Collapse Of A Bubble Cluster, Silvana Martini, Peter Birkin, Tadd T. Truscott

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Over the past decade several studies have reported the use of high intensity ultrasound (HIU) to induce the crystallization of lipids. The effect that HIU has on lipid crystallization is usually attributed to the generation of cavities but acoustic cavitation has never been fully explored in lipids. The dynamics of a particular cavitation cluster next to a piston like emitter in an oil, was investigated in this study. The lipid systems, which are important in food processing, are studied with high-speed camera imaging, laser scattering and pressure measurements. A sequence of stable clusters were noted. In addition, a bifurcated streamer …