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First Mesa, IA, United States

Coe College is a private, four-year, liberal arts college in Cedar Rapids, in the U.S. state of Iowa. Founded in 1851, the institution is historically affiliated with the Presbyterian Church . Its current president is David McInally. It is one of the smaller universities to have a chapter of Phi Beta Kappa. It is one of the Associated Colleges of the Midwest . Wikipedia.

Barney E.R.,University of Nottingham | Hannon A.C.,Rutherford Appleton Laboratory | Holland D.,University of Warwick | Umesaki N.,Osaka University | And 3 more authors.
Journal of Physical Chemistry Letters | Year: 2013

Understanding the structure of single-component glasses is essential for developing structural models of more complex multicomponent glasses. Currently, such models for tellurite systems are purely qualitative. This study presents neutron diffraction and Raman spectroscopy measurements of the structure of pure amorphous TeO2, showing that it is formed from a combination of two-thirds [TeO4] pseudo-trigonal bipyramids and one-third [TeO 3] trigonal pyramids with a terminal oxygen. This is in contrast to all crystalline polymorphs of TeO2, which are formed solely from the four-coordinated units. Using this result, a quantitative model has been developed that successfully predicts the average Te-O coordination number, nTeO, for a series of potassium tellurite glasses, xK 2O·(100 - x)TeO2. The observed nTeO is constant up to 15 mol % K2O due to the presence of terminal oxygen atoms in the tellurite network. © 2013 American Chemical Society.

Cottingham J.P.,Coe College
Proceedings of Forum Acusticum | Year: 2011

The acoustical properties of bamboo, along with its widespread availability, have made it one of the most commonly used materials for the construction of musical instruments worldwide. Bamboo has a relatively low density and elastic modulus, and a significant difference between the elastic moduli parallel to and perpendicular to the bamboo fibers. Since a wide variety of flutes and reed wind instruments employ bamboo pipes, the elastic moduli of bamboo pipes, as well as the non-uniformity of the pipe wall material are of current interest, in particular as related to pipe wall vibrations. Some recent results on measured physical properties of bamboo as used in Asian free reed wind instruments are presented, including mechanical properties of both bamboo reeds as well as pipes. Some investigations have been made of wall vibrations in the bamboo pipes of the Asian free-reed mouth organs, including both mechanically excited pipes and the blown reedpipe combinations. Measurements have also been made of changes occurring in pipe input impedance as a result of damping the vibrations of the bamboo pipe.

Cottingham J.,Coe College
Physics Today | Year: 2011

Free-reed instruments fall into two related but distinct families: Asian mouth organs of ancient origin and Western instruments that originated in Europe about 200 years ago. The Western free-reed instruments include the harmonica and the "squeezeboxes," the various forms of accordion and concertina. In their relatively short lifetime, those instruments in particular have come to be employed in almost all genres of music and, throughout the world, are among the most widely played. Yet until the late 20th century, only a small amount of acoustical research focused on free-reed instruments. During the past two or three decades, however, interest has surged, and researchers in musical acoustics have devoted a much greater amount of attention to them. To be sure, more papers are written about the trumpet, the clarinet, and the violin. But an indication of the increase in research interest in free reeds in the 1990s is the inclusion of a section in the second edition of The Physics of Musical Instruments (Springer, 1998), by Neville Fletcher and Thomas Rossing, that provides a summary of the research. The first edition of seven years earlier had no such section. © 2011 American Institute of Physics.

Hanwell M.D.,University of Pittsburgh | Hanwell M.D.,Kitware | Curtis D.E.,Coe College | Lonie D.C.,State University of New York at Buffalo | And 3 more authors.
Journal of Cheminformatics | Year: 2012

Background: The Avogadro project has developed an advanced molecule editor and visualizer designed for cross-platform use in computational chemistry, molecular modeling, bioinformatics, materials science, and related areas. It offers flexible, high quality rendering, and a powerful plugin architecture. Typical uses include building molecular structures, formatting input files, and analyzing output of a wide variety of computational chemistry packages. By using the CML file format as its native document type, Avogadro seeks to enhance the semantic accessibility of chemical data types. Results: The work presented here details the Avogadro library, which is a framework providing a code library and application programming interface (API) with three-dimensional visualization capabilities; and has direct applications to research and education in the fields of chemistry, physics, materials science, and biology. The Avogadro application provides a rich graphical interface using dynamically loaded plugins through the library itself. The application and library can each be extended by implementing a plugin module in C++ or Python to explore different visualization techniques, build/manipulate molecular structures, and interact with other programs. We describe some example extensions, one which uses a genetic algorithm to find stable crystal structures, and one which interfaces with the PackMol program to create packed, solvated structures for molecular dynamics simulations. The 1.0 release series of Avogadro is the main focus of the results discussed here. Conclusions: Avogadro offers a semantic chemical builder and platform for visualization and analysis. For users, it offers an easy-to-use builder, integrated support for downloading from common databases such as PubChem and the Protein Data Bank, extracting chemical data from a wide variety of formats, including computational chemistry output, and native, semantic support for the CML file format. For developers, it can be easily extended via a powerful plugin mechanism to support new features in organic chemistry, inorganic complexes, drug design, materials, biomolecules, and simulations. Avogadro is freely available under an open-source license from http://avogadro.openmolecules.net.

Cottingham J.,Coe College
Proceedings of Meetings on Acoustics | Year: 2013

The motion of air-driven free reeds used in the harmonica, accordion, and reed organ is dominated by the fundamental transverse beam mode, but higher transverse modes and the first torsional mode are usually present during steady oscillation, even at low amplitude. In addition a lateral mode has sometimes been detected, in which the reed tongue oscillation is perpendicular to the transverse oscillation. Interaction of the reed with a resonance in the instrument can result in unusual effects. In the accordion, resonances of the reed cavity can interfere with the reed self-excitation mechanism. In the harmonica, when the reed is nearly closed, a strong aerodynamic instability can in some cases lead to torsional flutter. A characteristic of some free reed instruments is a slow attack, in which the sound builds gradually and often unevenly, with the effect being greater for the longer, lower-pitched reeds. There is evidence that the first torsional mode and the second transverse mode may be significant in initiating reed oscillation, so that reed design enhancing the torsional mode may be helpful in alleviating the problem of slow attack. © 2013 Acoustical Society of America.

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