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Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

University of Arkansas, Fayetteville

2015

Journal

Articles 1 - 11 of 11

Full-Text Articles in Physical Sciences and Mathematics

The Effect Of Turning Frequency On In-Vessel Compost Processing And Quality, Paige E. Boyle, Mary C. Savin, Lisa S. Wood Jan 2015

The Effect Of Turning Frequency On In-Vessel Compost Processing And Quality, Paige E. Boyle, Mary C. Savin, Lisa S. Wood

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Composting can contribute to the zero waste initiative on the University of Arkansas (UA) campus. In-vessel systems like Earth Tubs™ are purported to provide better control of temperature and moisture during the composting process. Turning materials helps facilitate microbial activity and thermophilic composting. The goal of this research was to determine if turning frequency affects processing or final quality of compost made with pre- and post-consumer food waste feedstock and a wood chip bulking agent. Turning frequencies (treatment) of 3 days/week and 7 days/ week were evaluated simultaneously throughout three sequential runs. Temperature, pH, electrical conductivity (EC), and moisture content …

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Impact Of Environmentally Friendly Packaging On Consumers’ Attitudes And Patronage Intentions Toward Apparel Retail Brands, Madalyn M. Smith, Eunjoo Cho Jan 2015

Impact Of Environmentally Friendly Packaging On Consumers’ Attitudes And Patronage Intentions Toward Apparel Retail Brands, Madalyn M. Smith, Eunjoo Cho

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Consumer interest in social responsibility (SR) has greatly increased in recent years. Providing environmentally friendly packaging (recycled and reusable bags) is one example of how apparel retail brands can engage in SR. The objective of this research was to explore the impact of using environmentally friendly packaging on consumers’ attitudes and patronage intentions toward apparel retail brands. To conduct this research, undergraduate and graduate students from a major mid-Southern university completed an online survey testing consumers’ perceptions, environmental consciousness, attitudes, and patronage intentions. Results from this study revealed that young consumers’ perceptions of environmentally friendly packaging has a positive impact …

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Earthworm Populations In A Wheat-Soybean Double-Crop System Under Seven Years Of Established Residue Management Practices, Jill Thomason, Mary Savin, Kristopher Brye, Donn T. Johnson Jan 2015

Earthworm Populations In A Wheat-Soybean Double-Crop System Under Seven Years Of Established Residue Management Practices, Jill Thomason, Mary Savin, Kristopher Brye, Donn T. Johnson

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Earthworms improve soil structure, distribute litter and microbes, stimulate microbial activity, facilitate decomposition, and increase nitrogen (N) availability for plant growth. Earthworm density is often reduced in low organic matter soils that are intensively managed to grow row crops. This study was designed to relate earthworm density and community composition to residue management after seven years of established management practices in a wheat (Triticum aestivum L.)-soybean (Glycine max (L.) Merr.) double-crop system maintained in Marianna, Ark. Residue management practices included conventional tillage (CT) and no-tillage (NT), N fertilization to produce high and low wheat residue amounts left in the field, …

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Habitat Assessment And Ecological Restoration Design For An Unnamed Tributary Of Stone Dam Creek, Conway, Arkansas, Paige E. Boyle, Mary C. Savin, James A. Mccarty, Marty D. Matlock Jan 2015

Habitat Assessment And Ecological Restoration Design For An Unnamed Tributary Of Stone Dam Creek, Conway, Arkansas, Paige E. Boyle, Mary C. Savin, James A. Mccarty, Marty D. Matlock

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Urbanization can lead to increased sedimentation, erosion, pollution, and runoff into streams. The United States Environmental Protection Agency’s (USEPA) Rapid Bioassessment Protocols (RBPs) are sets of guidelines that can be used to assess a habitat’s sedimentology, hydrology, vegetation, and geomorphology to determine impairment. An unnamed tributary of Stone Dam Creek on the University of Central Arkansas (UCA) campus in Conway, Arkansas runs partially underground and through the urbanized UCA campus watershed. The stream was assessed using the USEPA’s RBPs to determine impairment of the stream, and received a RBP score of 71.2 out of 200 compared to 153.5 in a …

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Wave Profile For Anti-Force Waves With Maximum Possible Currents, M. Hemmati, R. Horn, W. P. Childs, A. K. Meredith Jan 2015

Wave Profile For Anti-Force Waves With Maximum Possible Currents, M. Hemmati, R. Horn, W. P. Childs, A. K. Meredith

Journal of the Arkansas Academy of Science

In the theoretical investigation of the electrical breakdown of a gas, we apply a one-dimensional, steady state, constant velocity, three component fluid model and consider the electrons to be the main element in propagation of the wave. The electron gas temperature, and therefore the electron gas partial pressure, is considered to be large enough to provide the driving force. The wave is considered to have a shock front, followed by a thin dynamical transition region. Our set of electron fluid-dynamical equations consists of the equations of conservation of mass, momentum, and energy, plus the Poisson's equation. The set of equations …

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Natural Nutrient Sources In The Cache River Watershed, Arkansas, M. K. Kilmer, N. Poe, S. Chappell, J. L. Bouldin Jan 2015

Natural Nutrient Sources In The Cache River Watershed, Arkansas, M. K. Kilmer, N. Poe, S. Chappell, J. L. Bouldin

Journal of the Arkansas Academy of Science

The growth of the hypoxic ‘dead zone’ in the Gulf of Mexico in recent years has placed increased focus on potential sources of nutrient pollution, with most of the focus being placed on watersheds where practices, including fertilizer application and land alterations combine to increase non-point source runoff. In this study, nutrient concentrations in surface waters of altered and unaltered areas of the Cache River Watershed, Arkansas, were compared to determine if agricultural land usage was responsible for the majority of nutrient inputs. Results suggest that for dissolved nitrites and orthophosphates, agricultural (altered) sites contribute significantly more than relatively unaltered …

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Development Of Heterogeneous Photosensitized Transition Metal Oxide Water-Splitting Catalysts On Silica Support, M. P. Gajewski, H. J. Crane, M. W. Nelson Jan 2015

Development Of Heterogeneous Photosensitized Transition Metal Oxide Water-Splitting Catalysts On Silica Support, M. P. Gajewski, H. J. Crane, M. W. Nelson

Journal of the Arkansas Academy of Science

The research presented in this manuscript describes the development of photosensitized inexpensive catalysts based on readily available materials. The investigation covers synthesis and characterization of photosensitizers based on porphyrins, mechanical and thermal coating of solid support with semiconducting transition metal oxides, photosensitization of the semiconducting layer, and characterization of the photoelectrochemical properties displayed by the new materials. The process of water oxidation is of primary interest here, with little emphasis put on reduction of protons to gaseous hydrogen. Photoelectrochemically produced protons serve as a probe of effectiveness of the catalysts. Several systems are described, and two catalysts are identified as …

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Bond Length - Bond Valence Relationships For Carbon - Carbon And Carbon - Oxygen Bonds, C. Harris, F. D. Hardcastle Jan 2015

Bond Length - Bond Valence Relationships For Carbon - Carbon And Carbon - Oxygen Bonds, C. Harris, F. D. Hardcastle

Journal of the Arkansas Academy of Science

In the present study, relationships are developed for determining bond orders (also referred to as bond valences or bond numbers) from published bond lengths for carbon-carbon (C-C) and carbon-oxygen (C-O) bonds. The relationships are based on Pauling’s empirical formula s = exp((Ro-R)/b)), where s is the bond order, R is the corresponding bond length, Ro is the unit valence bond length, and b is a fitting parameter. We use a recently derived relationship for the b parameter in terms of the bonding atoms’ published atomic orbital exponents. The resulting equations were checked against published x-ray diffraction (XRD) data for 176 …

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Low-Level Mercury Causes Inappropriate Activation In T And B Lymphocytes In The Absence Of Antigen Stimulation, K. L. Weigand, J. L. Reno, B. M. Rowley Jan 2015

Low-Level Mercury Causes Inappropriate Activation In T And B Lymphocytes In The Absence Of Antigen Stimulation, K. L. Weigand, J. L. Reno, B. M. Rowley

Journal of the Arkansas Academy of Science

The immune system primarily utilizes two cell types for adaptive immunity: T lymphocytes and B lymphocytes. T lymphocytes are activated when antigen presenting cells (APCs) present antigen to membrane-bound T cell receptors. B lymphocytes are activated when an antigen binds to receptors embedded in the plasma membrane. In both T and B cells this antigen binding crosslinks the receptor complexes and initiates the signal transduction cascade. These cascades frequently consist of a series of intracellular molecules becoming phosphorylated in a step-wise fashion. Once activated, these cells differentiate into effector cells that clear out the stimulating antigen. Mercury, which is a …

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Aquatic Effects Of A Localized Oil Spill On Lake Conway, Ar And Its Tributaries, M. E. Kennon, J. L. Bouldin Jan 2015

Aquatic Effects Of A Localized Oil Spill On Lake Conway, Ar And Its Tributaries, M. E. Kennon, J. L. Bouldin

Journal of the Arkansas Academy of Science

Oil spills, no matter where they occur, elicit environmental concern and avoiding these disasters should be a priority. Old pipelines that are not regularly maintained and carry large amounts of crude oil long distances are of particular concern. One such pipeline is the 65 year-old Pegasus pipeline owned by ExxonMobil. On March 29, 2013, 795,000 L of Wabasca Heavy Canadian crude oil spilled into a neighborhood of Mayflower, Arkansas, when the Pegasus pipeline ruptured. This spill led to the evacuation of many homes in the surrounding neighborhood. Drainage ditches in the affected neighborhood drained oil into a nearby cove of …

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A New Design Method For Vanadium Redox Batteries In Renewable Energy Systems, Casey Gibson, Karla G. Morrissey Unversity Of Arkansas, Fayetteville Jan 2015

A New Design Method For Vanadium Redox Batteries In Renewable Energy Systems, Casey Gibson, Karla G. Morrissey Unversity Of Arkansas, Fayetteville

Inquiry: The University of Arkansas Undergraduate Research Journal

This study investigated the behavior of vanadium redox flow batteries (VRFBs), which are batteries capable of easily switching between charging and discharging modes, making them a suitable option for storing intermittent sources of alternative energies (solar, wind, etc). Since different sizes of the battery provide varying voltages, optimal parameters for a particular home are key for implementation. These parameters, specifically the cell and tank volumes of the battery that are capable of providing consistent on-load voltage, were determined using data from a 13 kW solar array and a medium-sized house. Charge/discharge current values were used to run a mathematical model …

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