Fourteenth Annual Student Research Symposium
Thursday, March 14, 2013
Session 2
Pendergraft Library 300 South
| Time | Presenter | Mentor | Title of the Presentation |
| 9:00-9:15 | Jesse Lobbs | Christopher Duerringer |
AMERICAN AGAINST AMERICA: THE ACCUSATORY SPEECH OF JULIAN ASSANGE |
| 9:15-9:30 | Myles Hartman | Chris Kellner |
Avian Population Responses to Drought and Temperature in the Ouachita National Forest |
| 9:30-9:45 |
Marvin W. Suggs Jr., James Grisham, Natalie Larson, Josh Reed, Justin Nelson |
Mark Ballin, Yiannis Papelis, Menion Croll, Mike Guminsky and Mostafa HemmatiMark Ballin, Yiannis Papelis, Menion Croll, Mike Guminsky and Mostafa Hemmati |
INVESTIGATION OF A NETWORKED AIR TRAFFIC INFRASTRUCTURE VALIDATION ENVIRONMENT FOR DISTRIBUTED AIR/GROUND NEXT-GEN CONCEPTS |
| 9:45-10:00 | Matthew Wyatt and Zach Hutcheson | Fred Minetto, and Mostafa Hemmati |
LPSA AT GODDARD SPACE FLIGHT CENTER: CLEANING LENSES & MIRRORED SURFACES WITH ELECTRON GUN |
| 10:00-10:15 | Paul Pinkston and Joseph Rios |
Parimal Kaperdekar and Mostafa Hemmati |
MAPPING OVERLAY OF SURFACE ENVIRONMENTS FOR NEXTGEN AIRSPACE SYSTEMS |
| 10:15-10:30 | Xiaohan Du | Anwar A. Bhuiyan |
SYNTHESIS AND CHARACTERIZATION OF RUTHENIUM MONOMER AND DIMER COMPLEXES CONTAINING PHENANTHROLINE AND CHLORO-PHENANTHROLINE |
| 10:30-10:45 | Jennifer Brownfield, Stephanie Huaranga, Kyle Manning, Kayla Osborne, Johnny Sain, Tim Walton and Morgan Womack | Joshua Lockyer |
SUSTAINABLE FOOD SYSTEMS IN THE OZARK-OUACHITA REGION: OPPORTUNITIES, OBSTACLES, AND RESOURCES – AN OVERVIEW OF COLLECTIVE, INTERDISCIPLINARY RESEARCH |
| 10:45-11:00 | Zachary W. Freeman and Chelsea Whetstine | Genet Ide Duke |
PETROLOGY AND GEOCHEMISTRY OF THE RATTLESNAKE HILLS ALKALIC IGNEOUS INTRUSIVE COMPLEX |
| 11:00-11:15 | Chad Smith | Hamed Shojaei |
INTERACTING DARK ENERGY MODELS WITH CONSTANT INTERACTION |
| 11:15-11:30 | Summer Laffoon | Franklin D. Hardcastle |
RELATIONSHIP BETWEEN SILICON-OXYGEN BOND VALENCE AND BOND LENGTH |
| 11:30-11:45 | Joshua Pennington | R.J. Tackett |
Variant Crystal Lattice Structure of -Fe2O3 Under Successive Loadings into an Alginate Polymer Matrix |
| 11:45-12:00 | Rachel Pennington | Scott Kirkconnell and Shellie Hanna shanna |
THE ACUTE EFFECTS OF EXERCISE ON COGNITIVE FUNCTION |
| 12:00-1:00 | Lunch Break | ||
| 1:00-1:15 | Myles Hartman and Amanda Bradbury | Tsunemi Yamashita |
AN INVESTIGATION OF SCORPION TOXIN GENE VARIABILITY AMONG POPULATIONS |
| 1:15-1:30 | Mariah Small Nicholas Bailey | Ivan H. Still |
Use of high-throughput RNA sequencing to reveal TACC2s-mediated blocks to myoblast differentiation |
| 1:30-1:45 | Robert Bowman and Mollie Whihtehead | Charles Mebi |
Ruthenium Nitrosyl complexes: potential anticancer agents |
| 1:45-2:00 | Dacen Waters | Richard Howard and Mostafa Hemmati |
A MICRO-FRICTION TEST PLATFORM FOR SIMULATING RENDEZVOUS AND CAPTURE |
| 2:00-2:15 | Jesse Christensen | Mostafa Hemmati |
BREADOWN WAVES WITH CURRENT BEHIND THE SHOCK FRONT |
| 2:15-2:30 | Haley Morris | Mostafa Hemmati |
WAVE PROFILE FOR LIGHTNING RETURN STROKE |
| 2:30-2:45 | Hannah Conner | Molly Brant and Alvin Williams |
Reasons for Dairy Production Decline in Arkansas |
|
2:45-3:00 |
Louise McMinn |
Molly Brant and Alvin Williams |
Reasons for Dairy Production Continuation in Arkansas |
| 3:00-3:15 | Devon Dodd | Frank Hardcastle | TITANIUM – OXYGEN BOND LENGTH – BOND VALENCE RELATIONSHIP |
| Time | Presenter | Project | Project Director |
| 9:00-9:15 | Hunter Mullins | The Paranoid Apocalyptic Style of Rhetoric as Precursor to Violence | Dr. Thomas Vaughn,
Speech Theatre And Journalism |
| 9:20-9:35 | Rachel Forbes | Stress and Its Physiological Effects on the Immune System | Dr. Cynthia Jacobs,
Biological Sciences |
| 9:40-9:55 | Andy Jones | Overview of Electrochemistry | Dr. Stephen Gann,
Physical Sciences |
| 10:00-10:15 | Nick Kuburich | Chromatin's Essential Aspect in Development of Eukaryotic Organisms and Formation in Cancer | Dr. Ivan Still,
Biological Sciences |
| 10:20-10:35 | Robert Bowman,
(With Jonathan Curlin and Mollie Whitehead |
Manipulations of the Structure of Ruthenium Nitrosyl Complexes and Effects of Attached Ligand on the Release of Nitric Oxide from the Molecule | Dr. Charles Mebi,
Physical Sciences |
| 10:40-10:55 | Eli Virden | The Zombie Gallery | Dr. Erin Clair,
English |
| 11:00-11:15 | Rachel Pennington | The Acute Effects of Exercise on Cognitive Performance on Older Adults | Dr. Scott Kirkconnell,
Biological Sciences; Dr. Shellie Hanna, Curriculum and Instr |
| 11:20-11:35 | Aaron Wilkes | Visual Lies: How Your Brain isn't Telling You the Truth About the World Around You | Dr. Scott Kirkconnell,
Biological Sciences |
| 11:40-12:00 | Emily Slape | Sundown Towns in Northwest Arkansas | Dr. Thomas DeBlack,
History |
| 12:00-1:00 | LUNCH BREAK | ||
| 1:00-1:15 | Katie Nicholson | Social Media: Leveraging to Your Advantage | Dr. Jim Walton,
Management and Marketing |
| 1:20-1:35 | Matt Ferren | Corporate Social Responsibility in the Fast Food Industry | Dr. Jim Walton,
Management and Marketing |
9:00-9:15
This paper intends to present two speeches of Julian Assange and examine the rhetorical substance of the texts. It will do this through close textual analysis, a method in rhetorical studies that is employed to help us understand how stylistic and argumentative features of a text serve persuasive ends. From a modern rhetorical perspective, a public address, or oration, is best examined when situated in the context of ongoing ideological, historical, and stylistic concerns that constitute themselves temporally as a constellation of rhetorical fragments, which are best understood drawn from the text itself. The text functions as an anchor methodologically for the rhetorical critic to observe these elements. In these texts, Assange brings forth grave accusations about the United States, while at the same time effectively telling an American story. Simultaneously, Assange is able to accuse the United States of high crimes through values that have historically been claimed as "American". Assange's "Speech from the Ecuadorian Embassy" and "September Address to the United Nations" show the power an oration can have when time (and by extension, appropriateness) plays a crucial element in accusatory speech.
9:15-9:30
Over the past three years Arkansas has experienced a drought between June to August. In addition, temperatures in Arkansas are rising and 2012 was the hottest year on record. Because temperature and rainfall are known to impact avian populations, the objective of the research was to evaluate the impact of variation in temperature and rainfall on avian population fluctuations in the Ouachita National Forest.
Avian censuses were collected from 1997 and 2012 by Dr. Kellner at 25 locations between 15 May and 15 June within the Ouachita National Forest. This analysis focuses on nine avian species that are commonly found in the Ouachita National Forest. Temperature and precipitation data were obtained from the national climate data center at http://www.ncdc.noaa.gov. Monthly average temperature and rainfall were used in all analyses. In addition, percentage of rain days per month, and longest period with no rain were also examined. Stepwise linear regression was used to select the best combination of temperature and rainfall variables to predict each avian species' population response
Temperature and precipitation have had an effect on six of the nine species with four of these species being affected by both temperature and precipitation. However, the pattern of influence varies among the species, some are influenced by winter temperatures and other species are most influenced by a combination of winter and spring temperature. A few species were influenced by back to back months while others were affected by a single month and the same month the year before. Future results will give more information on how these species are affected and if other species are being affected in different ways.
It is commonly accepted that Automatic Dependent Surveillance – Broadcast (ADS-B) technology can transform the national airspace system (NAS) by increasing capacity, efficiency and safety. Although ADS-B has a promise of making great strides toward improving the national airspace system, there is resistance to the implementation of ADS-B technology due to financial, political and essentially a lack of acceptance of the value of this technology. NASA has been asked to help assist in closing the gap by further evaluating this technology, but flight tests to demonstrate this technology would be very expensive for participating parties and it would be impractical to test the advanced air traffic management concepts on a large and complex scale. A possible solution to this problem is to begin developing a validation approach and enabling infrastructure that will reduce costs of flight tests and will effectively validate the ADS-B standards requirements. The use of a Networked Air Traffic Infrastructure Validation Environment (NATIVE) has been investigated and proven to be technically feasible to implement for flight tests. To test advanced NASA concepts of operations, NATIVE utilizes in-flight data links to emulate ADS-B data essential to application specific guidance algorithms. A proof of concept demonstration of Flight Deck Based Interval Management (FIM) was recently performed at NASA Langley Research Center employing current NASA flight simulation software, Airspace and Traffic Operation Simulation (ATOS). Using the Aircraft Simulation for Traffic Operation Research (ASTOR), the transfer of data from existing avionics systems to flight hardware was demonstrated. An internet module was incorporated into ASTOR to simulate the effects of latency and the impact of ADS-B messages being lost completely in transmission. Preliminary results show that the FIM algorithm can indeed operate using in-flight internet; being able to endure a maximum mean latency of 25 seconds.
9:45-10:00
One of the major problems with space telescopes is maintaining a contamination free surface. Through the use of an electron gun, fractals, collection coil and fractal backstops, dust can be removed and collected in a more desired location. The electron gun creates a negative charge on the contamination and the fractals produce an electric field. This causes enough electrostatic repulsion and electromagnetic attraction to move dust contamination away from the original surface and onto the positively charged fractal backstops. This has been successfully tested in a vacuum in summer of 2012 and future work will focus on using this method of contamination mitigation at a pressure of one atmosphere for use in cleanrooms
Alaska is home to the some of the most hazardous flying conditions in the U.S. due to the extreme terrain and un-predictable climate. These natural elements combine to place general aviation pilots in the state of Alaska at substantial risk. In an effort to address this risk, NASA has partnered with the Alaskan Aviation Safety Program (AASP) in order to develop TAIGA (Traffic and Atmospheric Information for General Aviation). TAIGA is a future Android app that will use currently existing information infrastructures throughout Alaska to relay up-to-date flight conditions and situational data to the pilot via an Android device such as a tablet. The TAIGA software will also incorporate a PARALLAX Prop Stick-based microcontroller that will utilize Bluetooth to interact with the Android device and further increase the accuracy of the TAIGA system.
10:15-10:30
The study of photophysical and photochemical properties of ruthenium complexes is of great interest because of fundamental practical reasons. Ruthenium complexes have been investigated for use in artificial photosynthesis. This presentation deals with the synthesis and spectroscopic investigation of custom designed ruthenium complexes containing phenanthroline and chloro-phenanthroline ligands. These complexes may be useful for biological electron transfer studies. Heteroleptic ruthenium monomer complex Ru(phen)2(Cl-phen) (where phen = 1,10-phenanthroline and Cl-phen = 5-chloro-1,10-phenanthroline) was prepared in a two-step procedure previously developed in our laboratory. This monomer complex was used to prepare the ruthenium homometallic dimer complex, (phen)2Ru(phen-phen)Ru(phen)2, by utilizing the Ni-catalyzed coupling reaction. Both of the complexes were purified by extensive column chromatography. The identity and the integrity of the complexes were confirmed by elemental analysis. The calculated and the experimental values for the elemental analysis were compared to find the integrity of the prepared complexes. UV/Vis absorption, emission spectroscopic method, and cyclic voltammetric method were used to investigate the properties of these complexes.
10:30-10:45
Regional food economies are emerging around the world to provide additional food security and to conserve and enhance local cultural, natural, economic, and agricultural resources. An emerging body of interdisciplinary research suggests that developing regional food economies is an important strategy for local economic revitalization, cultural renewal, and ecological restoration. In light of this global trend and the emerging body of research addressing it, this applied research project is driven by the following question: What are the opportunities, obstacles, and resources for developing a regional food system in the Ozark-Ouachita region of northwest Arkansas and surrounding areas? In order to address this question, student researchers will conduct literature reviews and collect and analyze data in seven topical areas: 1) Regional Food Systems Around the World, 2) Food System History in the Ozark-Ouachita Region, 3) Farmers and Regional Identity 4) Consumer Decision Making, 5) Participants in the Sustainable Food and Agriculture Movement in the Ozark-Ouachita Region, 6) Agricultural Extension Agents, and 7) Mapping the Ozark-Ouachita Regional Food System. In this group presentation, seven student researchers will discuss their approach to the research and present initial findings from literature reviews and preliminary data collection. Students from this group presentation will make full-length individual presentations at the 2014 symposium when the research is completed.
The Rattlesnake Hills intrusive complex of Natrona County, Wyoming, is composed of alkali and subalkalic igneous rocks estimated to be ~44 Ma (K/Ar radiometric ages of feldspars from a quartze latite and phonolite; Pekarek et al., 1974). Previous geochemical (major, minor, and Sr-Nd isotopic) analyses revealed two phases of magmatism: a central group of alkalic intrusions surrounded and preceded by intrusions of two silica-saturated felsic magmas (Hoch and Frost,1993). Latite, nepheline-rich phonolite, trachyte and alkalic mela-trachyte make up the central alkalic group, whereas quartz latite and rhyolite comprise the surrounding rock units. Previous Sr and Nd isotopic data from quartz latite and rhyolite were interpreted as the result of crustal
assimilation involving arc-type magmatism, and the central alkalic group was interpreted as a partial mantle melt derived from decompressional melting of lithospheric mantle from a subduction event (Hoch and Frost, 1993). The lithospheric mantle here and elsewhere in western North America shows evidence of chemical modification by evolution of fluid from a subducted oceanic plate. Our current research furthers the sampling and geochemical analyses of the variety of alkalic and subalkalic igneous rocks of the Rattlesnake Hills, Wyoming, and compares our data to other alkalic igneous centers of the region which have related carbonatite magmatism. Field work has revealed carbonatite magmatism where none was previously observed. Petrographic studies are currently underway.
11:00-11:15
Interacting dark energy models can provide a powerful tool to solve the Cosmic Coincidence Problem. Last year, Chad explored the properties of dark energy models and how they can be employed to address the Cosmic Coincidence Problem. In this presentation, after introducing the interacting models and their properties, Chad will focus on constant interactions. Constant interaction means that dark energy gets converted to matter at constant rate to keep the ratio of dark energy and dark matter balanced. We will study a model with constant interaction and compare the numerical calculations in the theory with the observed data from supernovae observations by WMAP. The possibility to employ this model to study the history of the evolution of universe will also be explored.
11:15-11:30
Pauling (1947) was the first to determine the "empirical" logarithmic dependence of bond order (s, valence) to bond length
where Ro is the bond length of unit valence and "b" is an empirical fitting parameter. Since then, "b" values were experimentally found to range from 0.32 to 0.42 for many bonds, and as high as 0.9 between soft and hard ions. A common practice, however, is to consider the "b" parameter as a universal constant equal to 0.37.
Recently, a theoretical expression has been derived for the "b" parameter which allows the systematic determination of bond valence – bond length correlations for any chemical bond from orbital exponents of hydrogen-like wavefunctions corresponding to the valence electrons. In the present work, the orbital exponent of silicon was determined by fitting the above equation to experimentally determined bond lengths for silicon-oxygen compounds. The orbital exponents for silicon and oxygen allowed us to determine the value of the "b" parameter for silicon-oxygen bonds.
11:30-11:45
γ-Fe2O3 is created by "loading" Iron (III) Oxide into an alginate polymer matrix.
The process involves dropping alginate polymer beads into an FeCl2 solution for two
hours, while being agitated by nitrogen gas on low flow. The Iron in the solution
bonds with the Oxygen in the polymer, creating Iron (III) Oxide. One cycle of the
alginate polymer beads through the FeCl2 solution is called one "loading". It has
already been observed that the magnetic properties of
γ-Fe2O3 change under increased number of loads. Samples of γ-Fe2O3 have been created
that have went through: 1,3,5, and 7 loadings. These samples will be analyzed using
the powder diffraction method in order to determine their crystal structure. The purpose
of this experiment is to determine how the crystal structure of γ-Fe2O3 changes under
increased loadings.
11:45-12:00
The human brain is the most integrative and complex part of the human body. Groundbreaking studies in neuroplasticity show that the brain is much more regenerative and subject to change than previously believed. We are now aware that individuals can substantially influence their own brain capabilities and function; new neurons can be developed through neurogenesis, and neuronal networks are continually modified and re-built. The number of neurons and their physical condition help the human brain increase memory retention, mental processing speed, and selective attention. This is especially important in older adults.
The primary focus of this study was to test the effects of acute aerobic exercise on cognitive functioning of adults over the age of 60. A second purpose was to emphasize that the positive neurological effects of exercise can start taking place immediately and that strenuous 6-month programs aren't the only way to get positive results. This is important because it encourages older adults to get active in order to prolong the amount of time they have leading a good quality life. The hypothesis is that memory retention, mental processing speed, and selective attention would acutely improve in the participants after they had exercised, in comparison to their cognitive state prior to exercise. Methods included having participants complete a timed Stroop test to evaluate cognitive performances both before and after exercise. The results from the test before and after exercise were compared, and all participants completed the post-exercise test with improved scores. The increase in cognitive ability was shown to be due to the physiological effects caused by the acute exercise protocol, directly relating exercise and improved cognitive function. This shows that the benefits of exercise can start taking place immediately and promote mental health and well being.
Centruroides vittatus is a species of scorpion that is common to Arkansas and Texas which is from the toxic Centruroides genus; however it only exhibits moderate toxic effects on humans. The reason for this research is to isolate the sodium toxin gene in this species with the purpose of characterizing and cataloging the gene's variation among different population. The primary goal of the project is to gain a viable understanding of how sodium toxin genes and proteins are different from those in the more toxic species. We focus on the sodium toxin as it is one of the best studied venom components in this genus.
Overnight cultures were grown from colonies previously isolated by former students. Plasmids were then extracted from these cultures using a plasmid kit. PCR was then performed on these plasmids using Na2 and Na4 primers to cleave them. A gel electrophoresis was then performed using both the plasmids and the PCR samples. A picture was taken of the gel to determine if the products were isolated properly. The samples were then placed in the freezer until ready to be sent to UAMS for DNA sequencing.
PCR products and plasmids have been isolated from cultures 676-20 through 676-4 excluding sample 676-5. All samples that have shown proper bands when run through gel electrophoresis. These samples are currently in the freezer until ready to be sent to UAMS for sequencing. Future plans include to isolate more plasmid and PCR products for sequencing and to use new primers to obtain different products.
1:15-1:30
The expression of the myoD gene is essential to muscle cell differentiation as it is involved in the early steps of programming myoblast precursors, and subsequent fusion of the myoblasts into muscle fibers. In cells that fail to express this gene, myoD transcriptional targets are not switched on and cells fail to differentiate. The transforming acidic coiled coil 2 (TACC2) protein also influences the differentiation of myoblasts. During myoblast differentiation, an alternative splicing event causes a switch in TACC2 isoform expression from a short isoform (TACC2s) to a long isoform (TACC2l). Failure to switch from TACC2s to TACC2l during development results in the inhibition of myoD at the transcriptional level and subsequent muscle differentiation is arrested. The nature of the interaction between TACC2s and myoD gene regulation is currently unknown. We now report the results of ultra-high-throughput RNA sequencing to identify genes regulated by TACC2s in differentiating myoblast cells. This analysis has identified disruptions in Notch, Wnt and STAT signaling pathways, and implicated potential "nodal" proteins through which the TACC2s protein perturbs muscle cell differentiation.
1:30-1:45
There is considerable interest in metal nitrosyl complexes that could deliver nitric oxide (NO) to a specific target upon irradiation. This interest is due to nitric oxide involvement in several physiological processes such as blood pressure regulation, neurotransmission, and inhibition of tumor growth. We are interested in the study of ruthenium nitrosyl complexes for application in photodynamic cancer chemotherapy. In this presentation, we will discuss the synthesis and characterization of two ruthenium nitrosyl complexes containing phosphine ligands. The effect of the ligands on the properties of the compounds has been examined using spectroscopic techniques and will be presented.
1:45-2:00
The growing accumulation of so-called 'space junk' (post-operational spacecraft) in Earth orbit is of increasing concern to NASA due to the threat space debris poses to spacecraft operating in those regions. To mitigate this threat, NASA seeks to attach solar sails to non-functional satellites, inducing enough drag to initiate de-orbit. This maneuver, which requires grappling passive targets, is uniquely problematic in the frictionless environment of space. We have developed a multi-agent test-bed to demonstrate robotic rendezvous, capture, and manipulation in a micro-friction environment using the Flight Robotics Laboratory (FRL) flat-floor. The three air-bearing platforms developed, designated Mini-Mobility Bases, are significantly smaller than the FRL's current micro-friction platforms. The increased maneuverability of the smaller bases expands the FRL's capability to accurately simulate interactions between smaller spacecraft.
2:00-2:15
The propagation characteristics of breakdown waves propagating in the opposite direction of the electric field force on electrons and with a significant current behind the wave front have been studied. The successful model, a one-dimensional, steady-state, three-fluid hydro-dynamical representation has been utilized to find analytical solutions for current bearing breakdown waves propagating into a non-ionized medium. The electron gas partial pressure is assumed to be the main element in driving the wave and the waves are considered to be shock fronted. The governing equations include the equations of conservation of mass, momentum, and energy, plus Poisson's equation.
Waves propagating in the opposite direction of the electric field force on electrons will possess different structure than those moving in the same direction as the direction of the electric force on electrons. For waves with a significant current behind the shock front, the equation of conservation of energy and Poisson's equation, as well as the shock condition on electron temperature have to be modified. For a range of experimentally measured current values, we have been able to integrate the set of electron fluid dynamical equation through the dynamical transition region of the wave.
2:15-2:30
For analytical solution of breakdown waves, we employ a one-dimensional, steady-state, three-component (electrons, ions, and neutral particles) fluid model. The basic set of equations consists of the equation of conservation of mass flux, equation of conservation of momentum, equation of conservation of energy, plus Poison's equation. The wave is considered to have a shock front and the electron gas partial pressure is considered to provide the driving force for the propagation of the wave.
This investigation involves breakdown waves for which a large current exists in the vicinity of the wave front. Existence of current behind the shock front alters the equation of conservation of energy, Poison's equation as well as the boundary condition on electron temperature. Considering a current behind the shock front, we have made appropriate modifications in our set of electron fluid dynamical equations. Using the modified shock conditions, we have been able to integrate the set of electron fluid dynamical equations for Antiforce waves (lightning return stroke). We will present the wave profile for electric field, electron velocity, electron temperature and electron number density within the dynamical transition region of the wave.
2:30-2:45
The research was proposed as a method in studying the decline and continuation in dairy production in hopes of shedding some light for the rest of the Arkansas agriculture industry. Finding the reasons why certain producers either stayed in production or exited production will help determine if the Arkansas government needs to get involved in the future to protect other industries.
2:45-3:00
The research was proposed as a method in studying the decline and continuation in dairy production in hopes of shedding some light for the rest of the Arkansas agriculture industry. Finding the reasons why certain producers either stayed in production or exited production will help determine if the Arkansas government needs to get involved in the future to protect other industries.
3:00-3:15
TITANIUM – OXYGEN BOND LENGTH – BOND VALENCE RELATIONSHIP
A bond length – bond valence correlation is a simple way of checking and evaluating molecular structures and is of great interest in chemistry, biology, geology, and material science. Pauling (1947) first determined an "empirical" logarithmic dependence of bond order (s, valence) to bond length
where Ro is the bond length of unit valence and "b" is an empirical fitting parameter. Since then, "b" values were experimentally found to range from as low as 0.25 and as high as 0.9. A common practice is to consider the "b" parameter a universal constant equal to 0.37.
Based on quantum mechanical arguments, a theoretical expression for the "b" parameter has recently been found by our research group. In the present study, experimentally determined Ti-O bond lengths (literature data) were used to determine the orbital exponent of titanium (based on a single exponential, hydrogen-like wavefunction); this value was then used to determine the "b" parameter for Ti-O bonds and, subsequently, the bond valence-bond length relationship for titanium-oxygen bonds.
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