Physical Sciences and Mathematics Commons^™

Spatial Distribution Of Harmful Trace Elements In Chinese Coals, Cao Qingyi, Ren Wenying, Liang Chaoming, Zhang Yufei, Yang Liu

Coal Geology & Exploration

The potential impact of harmful trace elements in coal on the ecological environment and human health is one of the hot topics in the fields of geochemistry and energy environment. Geochemical mapping plays an important role in the deep understanding of geochemical processes and their changing laws. However, previous studies have not provided the national geochemical maps of harmful trace elements in Chinese coals. In this study, the content data of 1 167 Be, 1 315 Co, 1 406 Cu, 1 191 Mo, 1 247 Th, and 1 390 Zn in Chinese coal samples are analyzed, and their average contents …

The War On Abandoned Trolleys Can Be Won. Here's How, Johan Barthelemy

SMART Infrastructure Facility - Papers

As more commercial precincts develop, we see more shopping trolleys abandoned far away from the shops they belong to. Programs are in place to tackle this issue but haven't solved the problem. We need a more sophisticated multi-pronged approach, including smart use of technology, to limit the number of abandoned trolleys and their impact.

Virtual Reality May Be The Next Frontier In Remote Mental Health Care, Shiva Pedram

SMART Infrastructure Facility - Papers

In recent years, experts have focused on finding better ways to improve remotely delivered mental health care. Now, virtual reality (VR) may pave the way for myriad new opportunities.

The Frequency Of Kozai–Lidov Disc Oscillation Driven Giant Outbursts In Be/X-Ray Binaries, Rebecca G. Martin, Alessia Franchini

Physics & Astronomy Faculty Research

Giant outbursts of Be/X-ray binaries may occur when a Be-star disc undergoes strong eccentricity growth due to the Kozai–Lidov (KL) mechanism. The KL effect acts on a disc that is highly inclined to the binary orbital plane provided that the disc aspect ratio is sufficiently small. The eccentric disc overflows its Roche lobe and material flows from the Be star disc over to the companion neutron star causing X-ray activity. With N-body simulations and steady state decretion disc models we explore system parameters for which a disc in the Be/X-ray binary 4U 0115+634 is KL unstable and the resulting time-scale …

Revealing The Structure Of The Outer Disks Of Be Stars, Robert Klement, Anthony C. Carciofi, Thomas Rivinius, Lynn D. Matthews, Rodrigo G. Vieira, Richard Ignace, Jon E. Bjorkman, B. C. Mota, Daniel M. Faes, A. D. Bratcher, M. Cure, Stanislav Stefl

Richard Ignace

Context. The structure of the inner parts of Be star disks (≲ 20 stellar radii) is well explained by the viscous decretion disk (VDD) model, which is able to reproduce the observable properties of most of the objects studied so far. The outer parts, on the other hand, are not observationally well-explored, as they are observable only at radio wavelengths. A steepening of the spectral slope somewhere between infrared and radio wavelengths was reported for several Be stars that were previously detected in the radio, but a convincing physical explanation for this trend has not yet been provided.

Aims. We …

Revealing The Structure Of The Outer Disks Of Be Stars, Robert Klement, Anthony C. Carciofi, Thomas Rivinius, Lynn D. Matthews, Rodrigo G. Vieira, Richard Ignace, Jon E. Bjorkman, B. C. Mota, Daniel M. Faes, A. D. Bratcher, M. Cure, Stanislav Stefl

ETSU Faculty Works

Context. The structure of the inner parts of Be star disks (≲ 20 stellar radii) is well explained by the viscous decretion disk (VDD) model, which is able to reproduce the observable properties of most of the objects studied so far. The outer parts, on the other hand, are not observationally well-explored, as they are observable only at radio wavelengths. A steepening of the spectral slope somewhere between infrared and radio wavelengths was reported for several Be stars that were previously detected in the radio, but a convincing physical explanation for this trend has not yet been provided.

Aims. We …

How Should Power Quality Be Reported?, Victor Gosbell, D Robinson, Victor Smith, Robert Barr

Robert Barr

Regulators are increasingly asking utilities to conduct 'quality control' surveys on selected parts of their power system to establish the level of power quality. This activity leads can lead to a vast amount of data and its reporting needs to be carefully thought out if desired insights are to be achieved. Three styles are identified as serving most purposes - Site, Network and Utility reporting. These are designed to give respectively all the data of one site, summary data for each monitored site in the network, and average values across the utility's system. The data analysis to be used in …

Can The Wet - State Conductivity Of Hydrogels Be Improved By Incorporation Of Spherical Conducting Nanoparticles?, Katharina Schirmer, Cody Wright, Holly Warren, Brianna C. Thompson, Anita F. Quigley, Robert M. I Kapsa, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

In nerve and muscle regeneration applications, the incorporation of conducting elements into biocompatible materials has gained interest over the last few years, as it has been shown that electrical stimulation of some regenerating cells has a positive effect on their development. A variety of different materials, ranging from graphene to conducting polymers, have been incorporated into hydrogels and increased conductivities have been reported. However, the majority of conductivity measurements are performed in a dry state, even though material blends are designed for applications in a wet state, in vivo environment. The focus of this work is to use polypyrrole nanoparticles …

Learning How To Be An Academic - The Story Of A New Academic In The Sciences, Danielle Skropeta

Danielle Skropeta

No abstract provided.

Tracers Of Chromospheric Structure.I. Ca Ii H&K Emission Distribution Of 13,000 F, G, And K Stars In Sdss Dr7 Spectroscopic Sample, J K. Zhao, Terry D. Oswalt, G Zhao, Q H. Lu, A L. Luo, L Y. Zhang

Aerospace, Physics, and Space Science Faculty Publications

We present chromospheric activity index SHK measurements for over 13,000 F, G, and K disk stars with high signal-to-noise ratio (>60) spectra in the Sloan Digital Sky Survey (SDSS) Data Release 7 (DR7) spectroscopic sample. A parameter δS is defined as the difference between SHK and a “zero” emission line fitted by several of the most inactive stars. The SHK indices of subgiant stars tend to be much lower than dwarfs, which provide a way to distinguish dwarfs and giants with relatively low-resolution spectra. Cooler stars are generally more active and display a larger scatter than hotter stars. Stars …

Tracers Of Chromospheric Structure. I. Ca Ii H&K Emission Distribution Of 13,000 F, G, And K Stars In Sdss Dr7 Spectroscopic Sample, J. K. Zhao, T. D. Oswalt, G. Zhao, Q. H. Lu, A. L. Luo, L. Y. Zhang

Publications

We present chromospheric activity index S_HK measurements for over 13,000 F, G, and K disk stars with high signal-to-noise ratio (>60) spectra in the Sloan Digital Sky Survey (SDSS) Data Release 7 (DR7) spectroscopic sample. A parameter δS is defined as the difference between S_HK and a “zero” emission line fitted by several of the most inactive stars. The S_HK indices of subgiant stars tend to be much lower than dwarfs, which provide a way to distinguish dwarfs and giants with relatively low-resolution spectra. Cooler stars are generally more active and display a larger scatter than …

Meteoric 10Be, FeD, And Clay In Critical Zone Soils, Front Range, Colorado, Cianna Wyshnytzky, James Mccarthy

Cianna E Wyshnytzky

The critical zone is the zone within which meteoric water, atmospheric gases, soil, and bedrock interact, encompassing the zone of soil formation (Anderson et al., 2007). The concentrations of various pedogenic compounds at a given location indicate the degree of weathering that has taken place in the Critical Zone. Among the products of chemical weathering are secondary phyllosilicate minerals (clays) and iron (Birkeland, 1999). At stable sites, chronosequence studies have shown that the amount of pedogenic iron oxide and clay increase as soils become older (McFadden and Hendricks, 1985).

Meteoric ¹⁰Be is a cosmogenic nuclide produced from oxygen and nitrogen …

How Should Power Quality Be Reported?, Victor Gosbell, D Robinson, Victor Smith, Robert Barr

Dr Duane Robinson

No abstract provided.

Incorporation Of Radius-Info Can Be Simple With Simplemkl, Xinwang Liu, Lei Wang, Jianping Yin, Lingqiao Liu

Dr Lei Wang

Recent research has shown the benefit of incorporating the radius of the Minimal Enclosing Ball (MEB) of training data into Multiple Kernel Learning (MKL). However, straightforwardly incorporating this radius leads to complex learning structure and considerably increased computation. Moreover, the notorious sensitivity of this radius to outliers can adversely affect MKL. In this paper, instead of directly incorporating the radius of MEB, we incorporate its close relative, the trace of data scattering matrix, to avoid the above problems. By analyzing the characteristics of the resulting optimization, we show that the benefit of incorporating the radius of MEB can be fully …

High Resolution Compton Scattering Study Of Be, K. Hamalainen, S. Manninen, C. C. Kao, W. Caliebe, J. B. Hastings, A. Bansil, S. Kaprzyk, P. M. Platzman

Arun Bansil

We have carried out high-resolution Compton scattering measurements from two single crystals of Be ([00.1] and [11.0]), together with highly accurate all-electron first-principles computations of the profiles within the band theory framework. The Compton data were collected using a newly constructed crystal spectrometer at a record momentum resolution varying between 0.023 and 0.032 a.u. (full width at half maximum) with 8 keV x rays from a synchrotron source. Although the overall shapes of the measured and computed spectra are in good accord, the fine structure in the data shows significant discrepancies with respect to the local density approximation based theoretical …

International Observational Campaigns Of The Last Two Eclipses In Ee Cephei: 2003 And 2008/9, Cezary Galan, Peter Németh

Aerospace, Physics, and Space Science Faculty Publications

Context. EE Cep is an unusual long-period (5.6 yr) eclipsing binary discovered during the mid-twentieth century. It undergoes almost-grey eclipses that vary in terms of both depth and duration at different epochs. The system consists of a Be type star and a dark dusty disk around an invisible companion. EE Cep together with the widely studied ε Aur are the only two known cases of long-period eclipsing binaries with a dark, dusty disk component responsible for periodic obscurations. Aims. Two observational campaigns were carried out during the eclipses of EE Cep in 2003 and 2008/9 to verify whether the eclipsing …

The Thioflavin T Fluorescence Assay For Amyloid Fibril Detection Can Be Biased By The Presence Of Exogenous Compounds, Sean A. Hudson, Heath Ecroyd, Tak W. Kee, John A. Carver

Heath Ecroyd

Thioflavin T (ThT) dye fluorescence is used regularly to quantify the formation and inhibition of amyloid fibrils in the presence of anti-amyloidogenic compounds such as polyphenols. However, in this study, it was shown, using three polyphenolics (curcumin, quercetin and resveratrol), that ThT fluorescence should be used with caution in the presence of such exogenous compounds. The strong absorptive and fluorescent properties of quercetin and curcumin were found to significantly bias the ThT fluorescence readings in both in situ real-time ThT assays and single time-point dilution ThT-type assays. The presence of curcumin at concentrations as low as 0.01 and 1 uM …

Critical Differences And Clues In Eta Car's 2009 Event, Andrea Mehner, Kris Davidson, John C. Martin, Roberta M. Humphreys, Kazunori Ishibashi, Gary J. Ferland

Physics and Astronomy Faculty Publications

We monitored Eta Carinae with the Hubble Space Telescope WFPC2 and Gemini GMOS throughout the 2009 spectroscopic event, which was expected to differ from its predecessor in 2003. Here we report major observed differences between events and their implications. Some of these results were quite unexpected. (1) The UV brightness minimum was much deeper in 2009. This suggests that physical conditions in the early stages of an event depend on different parameters than the "normal" inter-event wind. Extra mass ejection from the primary star is one possible cause. (2) The expected He II λ4687 brightness maximum was followed several weeks …

N Ii Λλ5668−5712: A New Class Of Spectral Features In Eta Carinae, Andrea Mehner, Kris Davidson, Gary J. Ferland

Physics and Astronomy Faculty Publications

We report on the N II λλ5668-5712 emission and absorption lines in the spectrum of η Carinae. Spectral lines of the stellar wind regions can be classified into four physically distinct categories: (1) low-excitation emission such as H I and Fe II, (2) higher-excitation He I features, (3) the N II lines discussed in this paper, and (4) He II emission. These categories have different combinations of radial velocity behavior, excitation processes, and dependences on the secondary star. The N II lines are the only known features that originate in "normal" undisturbed zones of the primary wind but depend primarily …

A Sea Change In Eta Carinae, Andrea Mehner, Kris Davidson, Roberta M. Humphreys, John C. Martin, Kazunori Ishibashi, Gary J. Ferland, Nolan R. Walborn

Physics and Astronomy Faculty Publications

Major stellar-wind emission features in the spectrum of η Car have recently decreased by factors of order 2 relative to the continuum. This is unprecedented in the modern observational record. The simplest, but unproven, explanation is a rapid decrease in the wind density.

High-Excitation Emission Lines Near Eta Carinae, And Its Likely Companion Star, Andrea Mehner, Kris Davidson, Gary J. Ferland, Roberta M. Humphreys

Physics and Astronomy Faculty Publications

In order to study the distribution of gas and ionizing radiation around η Car and their implications for its likely companion star, we have examined high-excitation emission lines of [Ne III], [Fe III], etc., in spectra obtained with the Hubble Space Telescope/Space Telescope Imaging Spectrograph instrument during 1998-2004. Our principal results, some of them unexpected, are as follows. (1) The high-excitation fluxes varied systematically and non-trivially throughout η Car's 5.5 year spectroscopic cycle. Instead of rising to a plateau after the 1998 ''event,'' they changed continuously with a maximum in mid-cycle. (2) At one significant location a brief, strong …

Learning How To Be An Academic - The Story Of A New Academic In The Sciences, Danielle Skropeta

Faculty of Science - Papers (Archive)

No abstract provided.

The Thioflavin T Fluorescence Assay For Amyloid Fibril Detection Can Be Biased By The Presence Of Exogenous Compounds, Sean A. Hudson, Heath Ecroyd, Tak W. Kee, John A. Carver

Faculty of Science - Papers (Archive)

Thioflavin T (ThT) dye fluorescence is used regularly to quantify the formation and inhibition of amyloid fibrils in the presence of anti-amyloidogenic compounds such as polyphenols. However, in this study, it was shown, using three polyphenolics (curcumin, quercetin and resveratrol), that ThT fluorescence should be used with caution in the presence of such exogenous compounds. The strong absorptive and fluorescent properties of quercetin and curcumin were found to significantly bias the ThT fluorescence readings in both in situ real-time ThT assays and single time-point dilution ThT-type assays. The presence of curcumin at concentrations as low as 0.01 and 1 uM …

Proton‐Donor Properties Of Water And Ammonia In Van Der Waals Complexes. Be–H2o And Be–Nh3, G. Chalasinski, M. M. Szczesniak, Steve Scheiner

Steve Scheiner

The potential energy surfaces (PES) of Be–H₂O and Be–NH₃ are studied with particular attention to characterization of proton‐donor properties of water and ammonia. Calculations were performed by means of both supermolecular and intermolecular Møller Plesset perturbation theory. The Be–H₂O PES reveals two van der Waals minima: the C_2v minimum (D_e=176 cm⁻¹, R_e=6.5 bohr), and the H‐bonded minimum (D_e=161 cm⁻¹, R_e=7.5 bohr), separated by a barrier of 43 cm⁻¹ at the T‐shaped configuration. The Be–NH₃ PES reveals only …

Proton‐Donor Properties Of Water And Ammonia In Van Der Waals Complexes. Be–H2o And Be–Nh3, G. Chalasinski, M. M. Szczesniak, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

The potential energy surfaces (PES) of Be–H₂O and Be–NH₃ are studied with particular attention to characterization of proton‐donor properties of water and ammonia. Calculations were performed by means of both supermolecular and intermolecular Møller Plesset perturbation theory. The Be–H₂O PES reveals two van der Waals minima: the C_2v minimum (D_e=176 cm⁻¹, R_e=6.5 bohr), and the H‐bonded minimum (D_e=161 cm⁻¹, R_e=7.5 bohr), separated by a barrier of 43 cm⁻¹ at the T‐shaped configuration. The Be–NH₃ PES reveals only …