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Late Quaternary Faulting History Of The Carrizal And Related Faults, La Paz Region, Baja California Sur, Mexico, Paul J. Umhoefer, Sara J. Maloney, Beverly Buchanan, J. Ramón Arrowsmith, Genaro Martinez-Gutiérrez, Graham Kent, Neal Driscoll, Alistair Harding, Darrell Kaufman, Tammy M. Rittenour 2019 Northern Arizona University

Late Quaternary Faulting History Of The Carrizal And Related Faults, La Paz Region, Baja California Sur, Mexico, Paul J. Umhoefer, Sara J. Maloney, Beverly Buchanan, J. Ramón Arrowsmith, Genaro Martinez-Gutiérrez, Graham Kent, Neal Driscoll, Alistair Harding, Darrell Kaufman, Tammy M. Rittenour

Tammy M. Rittenour

The southwest margin of the Gulf of California has an array of active normal faults despite this being an oblique-divergent plate boundary with spreading centers that localized deformation along the plate boundary 2–3 million years ago. The Carrizal and Centenario faults form the western border fault of the Gulf of California marginal fault system within and south of La Paz Bay, and ∼20–30 km west of the capital city of La Paz, Baja California Sur, Mexico. Geologic and geomorphic mapping, optically stimulated luminescence (OSL) geochronology, and paleoseismic investigations onshore, compressed high-intensity radar pulse (CHIRP) profiling offshore, and analysis ...


Limits Of Luminescence Dating: An Update Regarding Quartz Of The Southern Alps Of New Zealand And The Olympic Mountains, Washington, Usa, Cianna E. Wyshnytzky, Tammy M. Rittenour 2019 tammy.rittenour@usu.edu

Limits Of Luminescence Dating: An Update Regarding Quartz Of The Southern Alps Of New Zealand And The Olympic Mountains, Washington, Usa, Cianna E. Wyshnytzky, Tammy M. Rittenour

Tammy M. Rittenour

Late Pleistocene glacial sediments from the South Fork Hoh River valley in the Olympic Mountains, Washington, USA and the Lake Hawea valley in the Southern Alps, New Zealand were dated using optically stimulated luminescence (OSL) on quartz and infrared stimulated luminescence (IRSL) on feldspar sand from 2011-2013. High sediment supply (typical of glacial environments), short transport distances, and sediment newly eroded from bedrock sources were expected to pose problems for luminescence dating in these locations. Samples were collected from a variety of depositional environments and inferred distances from the ice-front to assess how luminescence signals may vary due to these ...


A Tree-Ring Based Reconstruction Of Logan River Streamflow In Northern Utah, Eric B. Allen, Tammy M. Rittenour, R. Justin DeRose, Matthew F. Bekker, Roger Kjelgren, Brendan M. Buckley 2019 tammy.rittenour@usu.edu

A Tree-Ring Based Reconstruction Of Logan River Streamflow In Northern Utah, Eric B. Allen, Tammy M. Rittenour, R. Justin Derose, Matthew F. Bekker, Roger Kjelgren, Brendan M. Buckley

Tammy M. Rittenour

[1] We created six new tree-ring chronologies in northern Utah, which were used with preexisting chronologies from Utah and western Wyoming to reconstruct mean annual flow for the Logan River, the largest tributary of the regionally important Bear River. Two reconstruction models were developed, a “Local” model that incorporated two Rocky Mountain juniper chronologies located within the basin, and a “Regional” model that also included limber pine and pinyon pine chronologies from a larger area. The Local model explained 48.2% of the variability in the instrumental record and the juniper chronologies better captured streamflow variability than Douglas-fir collected within ...


Controls On Erosion In The Western Tarin Basin: Implications For The Uplift Of Northwest Tibet And The Parmir, Peter D. Clift, Hongbo Zheng, Andrew Carter, Philipp Böning, Tara N. Jonell, Hannah Schorr, Xin Shan, Katharina Pahnke, Xiaochun Wei, Tammy M. Rittenour 2019 Louisiana State University

Controls On Erosion In The Western Tarin Basin: Implications For The Uplift Of Northwest Tibet And The Parmir, Peter D. Clift, Hongbo Zheng, Andrew Carter, Philipp Böning, Tara N. Jonell, Hannah Schorr, Xin Shan, Katharina Pahnke, Xiaochun Wei, Tammy M. Rittenour

Tammy M. Rittenour

We present here bulk sediment major element chemistry, Nd and Sr isotope ratios, and detrital apatite fission-track (AFT) and U-Pb zircon ages to characterize the provenance of the southwestern Taklimakan Desert (northwest China) and the three major rivers draining this region. We establish the spatial and temporal controls on erosion and sediment transport in the modern Tibetan rain shadow. The Hotan River drains the North Kunlun block and is characterized by zircon populations at 160–230 Ma and 370–520 Ma. The Yarkand River shares these grains with the Hotan, but also has a very prominent zircon population at 40 ...


Age Of Barrier Canyon-Style Rock Art Constrained By Cross-Cutting Relations And Luminescence Dating Techniques, Joel L. Pederson, Melissa S. Chapot, Steven R. Simms, Reza Sohbati, Tammy M. Rittenour, Andrew S. Murray, Gary Cox 2019 Utah State University

Age Of Barrier Canyon-Style Rock Art Constrained By Cross-Cutting Relations And Luminescence Dating Techniques, Joel L. Pederson, Melissa S. Chapot, Steven R. Simms, Reza Sohbati, Tammy M. Rittenour, Andrew S. Murray, Gary Cox

Tammy M. Rittenour

Rock art compels interest from both researchers and a broader public, inspiring many hypotheses about its cultural origin and meaning, but it is notoriously difficult to date numerically. Barrier Canyon-style (BCS) pictographs of the Colorado Plateau are among the most debated examples; hypotheses about its age span the entire Holocene epoch and previous attempts at direct radiocarbon dating have failed. We provide multiple age constraints through the use of cross-cutting relations and new and broadly applicable approaches in optically stimulated luminescence dating at the Great Gallery panel, the type section of BCS art in Canyonlands National Park, southeastern Utah. Alluvial ...


Collaborative Research: Tespresso, Tectonic Encoding, Shredding, And Propagation Of Environmental Signals As Surficial Observables, Tammy M. Rittenour 2019 Utah State University

Collaborative Research: Tespresso, Tectonic Encoding, Shredding, And Propagation Of Environmental Signals As Surficial Observables, Tammy M. Rittenour

Tammy M. Rittenour

No abstract provided.


Effects Of Moisture Content And Solvent Additive On Headspace Solid-Phase Microextraction Of Total Petroleum Hydrocarbons From Soil, Mereke B. Alimzhanova, Bulat N. Kenessov, Mikhail Nauryzbayev, Jacek A. Koziel 2019 al-Farabi Kazakh National University

Effects Of Moisture Content And Solvent Additive On Headspace Solid-Phase Microextraction Of Total Petroleum Hydrocarbons From Soil, Mereke B. Alimzhanova, Bulat N. Kenessov, Mikhail Nauryzbayev, Jacek A. Koziel

Jacek A. Koziel

Present paper describes optimization of the method of quantitative determination of total petroleum hydrocarbons in soil samples using headspace solid - phase microextraction (SPME) in combination with gas chromatography - mass spectrometry (GC-MS). Effects of moisture content and solvent additives were studied. It was established that an increase of the moisture content in soil leads to an increase of the response of petroleum hydrocarbons reaching its maximum at 15-20% depending on the soil type and concentration of total petroleum hydrocarbons followed by its gradual decrease. For the same concentration of petroleum hydrocarbons, an increase of moisture content in soil from 0 to ...


International Journal Of Biology And Chemistry, Dina Orazbayeva, Bulat Kenessov, Jacek A. Koziel 2019 Al-Farabi Kazakh National University

International Journal Of Biology And Chemistry, Dina Orazbayeva, Bulat Kenessov, Jacek A. Koziel

Jacek A. Koziel

Development of simple, fast and accurate methods for quantification of volatile organic compounds (VOCs) in soil samples is important for providing greater efficiency of analytical laboratories in Kazakhstan and other developing countries. Naphthalene is a model polycyclic aromatic hydrocarbon (PAH), belonging to a group of compounds of significant concern due to environmental impact. Solidphase microextraction (SPME) is an optimal method for solvent-free automated sample preparation for determination of VOCs in environmental samples. In this work, the method for quantification of naphthalene in soil based on headspace SPME, gas chromatography with mass spectrometric detection, and standard addition calibration was developed. The ...


Random Walks On Digraphs, J.J.P. Veerman 2019 Portland State University

Random Walks On Digraphs, J.J.P. Veerman

J. J. P. Veerman

Let V = {1, · · · n} be a vertex set and S a non-negative row-stochastic matrix (i.e. rows sum to 1). V and S define a digraph G = G(V, S) and a directed graph Laplacian L as follows. If (S)ij > 0 (in what follows we will leave out the parentheses) there is a directed edge j → i. Thus the ith row of S identifies the edges coming into vertex i and their weights. This set of vertices are collectively the neighbors of i, and is denoted by Ni . The diagonal elements Sii are chosen such that each row sum ...


There And Back Again: A Chemist Tale & The Lord Of The Ring Stands, Benjamin Blass 2019 Temple University

There And Back Again: A Chemist Tale & The Lord Of The Ring Stands, Benjamin Blass

Science Seminars

Students at universities and colleges are focused on achieving their degrees, but often wonder where their careers will take them once they leave the confines of the academic world. While some people’s careers are straight lines through to retirement, others are wandering paths that lead to unexpected outcomes and opportunities. In an effort to provide some insight into life after school. This lecture describes Dr. Blass’s career journey over his 25+ year career and highlights some of the lessons he learned along the way.


Climate Warming Trends In The U.S. Midwest Using Four Thermal Models, Lori J. Abendroth, Fernando E. Miguez, Michael J. Castellano, Jerry L. Hatfield 2019 Iowa State University

Climate Warming Trends In The U.S. Midwest Using Four Thermal Models, Lori J. Abendroth, Fernando E. Miguez, Michael J. Castellano, Jerry L. Hatfield

Michael Castellano

Thermal time (TT) is an agro-climate index widely established and used in predicting plant development based on temperature. This index is a powerful tool for measuring multi-faceted changes in temperature occurring from climate change. In the present study, TT was calculated for the entire frost-free period and individual spring, summer, and fall seasons using growing degree day (GDD), general thermal index (GTI), crop heat unit (CHU), and heat stress degree day (HSDD) models for 1054 counties across 12 Midwest states on a daily basis from 1950 to 2017. The temporal trend for each county was fit with a linear regression ...


Supereulerian Graphs And The Petersen Graph, Ii, Zhi-Hong Chen, Hong-Jian Lai 2019 Butler University

Supereulerian Graphs And The Petersen Graph, Ii, Zhi-Hong Chen, Hong-Jian Lai

Zhi-Hong Chen

In this note, we verify two conjectures of Catlin in [J. Graph Theory 13 (1989) 465 - 483] for graphs with at most 11 vertices. These are used to prove the following theorem which improves prior results in [10] and [13]:

Let G be a 3-edge-connected simple graph with order n. If n is large and if for every edge 11.v E E(G), d(u) + d(v) 2 % - 2, then either G has a spanning eulerian subgraph or G can be contracted to the Petersen graph.


Fan-Type Conditions For Collapsible Graphs, Zhi-Hong Chen 2019 Butler University

Fan-Type Conditions For Collapsible Graphs, Zhi-Hong Chen

Zhi-Hong Chen

No abstract provided.


Simultaneous In Situ Measurements Of Small-Scale Structures In Neutral, Plasma, And Atomic Oxygen Densities During The Wadis Sounding Rocket Project, Boris Strelnikov, Martin Eberhart, Martin Friedrich, Jonas Hedin, Mikhail Khaplanov, Gerd Baumgarten, Bifford P. Williams, Tristan Staszak, Heiner Asmus, Irina Strelnikova, Ralph Latteck, Mykhaylo Grygalashvyly, Franz-Josef Lübken, Josef Höffner, Raimund Wörl, Jörg Gumbel, Stefan Löhle, Stefanos Fasoulas, Markus Rapp, Aroh Barjatya, Michael J. Taylor, Pierre-Dominique Pautet 2019 Rostock University

Simultaneous In Situ Measurements Of Small-Scale Structures In Neutral, Plasma, And Atomic Oxygen Densities During The Wadis Sounding Rocket Project, Boris Strelnikov, Martin Eberhart, Martin Friedrich, Jonas Hedin, Mikhail Khaplanov, Gerd Baumgarten, Bifford P. Williams, Tristan Staszak, Heiner Asmus, Irina Strelnikova, Ralph Latteck, Mykhaylo Grygalashvyly, Franz-Josef Lübken, Josef Höffner, Raimund Wörl, Jörg Gumbel, Stefan Löhle, Stefanos Fasoulas, Markus Rapp, Aroh Barjatya, Michael J. Taylor, Pierre-Dominique Pautet

Pierre-Dominique Pautet

In this paper we present an overview of measurements conducted during the WADIS-2 rocket campaign. We investigate the effect of small-scale processes like gravity waves and turbulence on the distribution of atomic oxygen and other species in the mesosphere–lower thermosphere (MLT) region. Our analysis suggests that density fluctuations of atomic oxygen are coupled to fluctuations of other constituents, i.e., plasma and neutrals. Our measurements show that all measured quantities, including winds, densities, and temperatures, reveal signatures of both waves and turbulence. We show observations of gravity wave saturation and breakdown together with simultaneous measurements of generated turbulence. Atomic ...


Simultaneous In Situ Measurements Of Small-Scale Structures In Neutral, Plasma, And Atomic Oxygen Densities During The Wadis Sounding Rocket Project, Boris Strelnikov, Martin Eberhart, Martin Friedrich, Jonas Hedin, Mikhail Khaplanov, Gerd Baumgarten, Bifford P. Williams, Tristan Staszak, Heiner Asmus, Irina Strelnikova, Ralph Latteck, Mykhaylo Grygalashvyly, Franz-Josef Lübken, Josef Höffner, Raimund Wörl, Jörg Gumbel, Stefan Löhle, Stefanos Fasoulas, Markus Rapp, Aroh Barjatya, Michael J. Taylor, Pierre-Dominique Pautet 2019 Rostock University

Simultaneous In Situ Measurements Of Small-Scale Structures In Neutral, Plasma, And Atomic Oxygen Densities During The Wadis Sounding Rocket Project, Boris Strelnikov, Martin Eberhart, Martin Friedrich, Jonas Hedin, Mikhail Khaplanov, Gerd Baumgarten, Bifford P. Williams, Tristan Staszak, Heiner Asmus, Irina Strelnikova, Ralph Latteck, Mykhaylo Grygalashvyly, Franz-Josef Lübken, Josef Höffner, Raimund Wörl, Jörg Gumbel, Stefan Löhle, Stefanos Fasoulas, Markus Rapp, Aroh Barjatya, Michael J. Taylor, Pierre-Dominique Pautet

Michael J. Taylor

In this paper we present an overview of measurements conducted during the WADIS-2 rocket campaign. We investigate the effect of small-scale processes like gravity waves and turbulence on the distribution of atomic oxygen and other species in the mesosphere–lower thermosphere (MLT) region. Our analysis suggests that density fluctuations of atomic oxygen are coupled to fluctuations of other constituents, i.e., plasma and neutrals. Our measurements show that all measured quantities, including winds, densities, and temperatures, reveal signatures of both waves and turbulence. We show observations of gravity wave saturation and breakdown together with simultaneous measurements of generated turbulence. Atomic ...


Connectivity Of Cycle Matroids And Bicircular Matroids, Zhi-Hong Chen, Kuang Ying-Qiang, Hong-Jian Lai 2019 Butler University

Connectivity Of Cycle Matroids And Bicircular Matroids, Zhi-Hong Chen, Kuang Ying-Qiang, Hong-Jian Lai

Zhi-Hong Chen

A unified approach to prove former connectivity results of Tutte, Cunningham, Inukai and Weinberg, Oxley and Wagner.


Forcibly-Biconnected Graphical Degree Sequences: Decision Algorithms And Enumerative Results, Kai Wang 2019 Georgia Southern University

Forcibly-Biconnected Graphical Degree Sequences: Decision Algorithms And Enumerative Results, Kai Wang

Theory and Applications of Graphs

We present an algorithm to test whether a given graphical degree sequence is forcibly biconnected. The worst case time complexity of the algorithm is shown to be exponential but it is still much better than the previous basic algorithm for this problem. We show through experimental evaluations that the algorithm is efficient on average. We also adapt the classic algorithm of Ruskey et al. and that of Barnes and Savage to obtain some enumerative results about forcibly biconnected graphical degree sequences of given length $n$ and forcibly biconnected graphical partitions of given even integer $n$. Based on these enumerative results ...


Complex Oscillatory Decrease With Size In Diffusivity Of {100}-Epitaxially Supported 3d Fcc Metal Nanoclusters, King C. Lai, James W. Evans 2019 Iowa State University and Ames Laboratory

Complex Oscillatory Decrease With Size In Diffusivity Of {100}-Epitaxially Supported 3d Fcc Metal Nanoclusters, King C. Lai, James W. Evans

James W. Evans

Diffusion and coalescence of supported 3D metal nanoclusters (NCs) leads to Smoluchowski Ripening (SR), a key pathway for catalyst degradation. Variation of the NC diffusion coefficient, DN, with size N (in atoms) controls SR kinetics. Traditionally, a form DN ∼ N−β was assumed consistent with mean-field analysis. However, KMC simulation of a stochastic model for diffusion of {100}-epitaxially supported fcc NCs mediated by surface diffusion reveals instead a complex oscillatory decrease of DN with N. Barriers for surface diffusion of metal atoms across and between facets, along step edges, etc., in this model are selected to accurately capture behavior ...


Panel 9. Paper 9.3: Connecting Social And Physical Boundaries Of The Commons : Study Of Kuhl Irrigation Systems Of Kangra, Amit Tandon 2019 University of Massachusetts Amherst

Panel 9. Paper 9.3: Connecting Social And Physical Boundaries Of The Commons : Study Of Kuhl Irrigation Systems Of Kangra, Amit Tandon

Rural Heritage - Landscapes and Beyond / PATRIMOINE RURAL: Paysages et au-delà

Water has been a lifeline of Indian agrarian society. The thriving agrarian economy requires water for irrigation and the need for resources to the evolution of indigenous technology through generations of communities. Kuhl irrigation system of Kangra is a community managed traditional irrigation systems found in western Himalayan. These are a centuries-old network of interconnected drainage channels that drain water from nearby khads (rivers) into the fields. The irrigation systems have codified customary laws, systems of collective action for maintenance and preservation and various traditional livelihoods.

Kuhls of Kangra is a unique case where the community is owned and managed ...


Effect Of Synthesized 3-Hydroxyflavone Solutions On The Performance Of Dye-Sensitized Solar Cells, Aarya Kapani, Hasitha Mahabaduge 2019 Georgia College and State University

Effect Of Synthesized 3-Hydroxyflavone Solutions On The Performance Of Dye-Sensitized Solar Cells, Aarya Kapani, Hasitha Mahabaduge

Georgia Journal of Science

We investigated the influence of synthesized dye combination 3-hydroxyflavone with potassium hydroxide and sodium hydroxide as photosynthesizers for dye-sensitized solar cells (DSSCs). DSSCs are classified as hybrid inorganic/organic photovoltaic cells that have been reported to have lower production costs and efficiency as high as 12%. Annealed titanium dioxide pastes on fluorine doped tin oxide was used as the front layer of the completed devices and the performance of 3-hydroxyflavone with potassium hydroxide and sodium hydroxide was compared with the performance of dyes extracted from berries. UV-vis spectroscopy was used to characterize the absorbance of the respective absorber dyes. 3-Hydroxyflavone ...


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