This file is automatically updated by the Web server after anyone submits an abstract by using the Online - Call for Papers. These abstracts will also appear in the detailed program for the meeting.
Papers to be Presented on Friday Afternoon
Interactive Examples and Web-based Homework. Tim Stelzer and Gary Gladding, University of Illinois, Urbana, IL 61801. Interactive Examples (IEs) are the latest advance in Web-based homework at the Department of Physics at the University of Illinois at Urbana-Champaign. The major improvement over previous Web-based homework servers is the addition of a powerful "help" driver that engages students in a Socratic dialog, designed to guide them through the problem's solution. We will present examples of IE homework, as well as a preliminary analysis of its effectiveness. We have also recently been awarded a grant to hold a one week summer workshop. This workshop will provide everything needed to allow any interested instructor to incorporate Interactive Examples into their curriculum.
Capacitance Bridge Measurements of Magnetostriction. Won-Chul Shin, David K. Rigsbee, and Mark S. Boley, Western Illinois University, Macomb, IL 61455. Magnetostriction Effects were investigated in three different materials by using a simple, cost-effective, and highly successful method just recently developed in our WIU Physics Department's Magnetoelasticity Laboratory. The magnetostriction effects were generated by a large oscillating magnetic field produced by a high current (up to 600A) 60Hz AC welder power supply. Then, the magnetostriction effects were detected by a change in capacitance occurring between the sample ring and a larger concentric brass ring; this capacitance change was monitored by a capacitance bridge meter. The output of the bridge was collected by a storage cathode-ray oscilloscope and its voltage versus time signals were analyzed by a computer program. Two ferromagnetic high-speed steel rings, of material numbers 4620 and 4340, were used as the samples for the magnetostriction effects, and an aluminum ring, which is a paramagnetic material, was used for the control sample. LabView, Microsoft Excel, and a C program were used to analyze the data transferred from the storage CRO to the computer. This study showed that the 4340 ring, which had a higher nickel content than that of the 4620 ring, had the largest magnetostriction effect, and the aluminum ring showed no magnetostriction effect, as was expected. This experimental method has been shown to be sufficient to classify most types of steels in terms of their magnetostriction effects (normally rated in ppm) with only minor limitations.
Well-width and Temperature Dependence of Photoluminescence Energies in a Semiconductor Multiple Quantum Well Heterostructure. Daniel A. Johnson, Laurie A. Pichla, and Mark S. Boley, Western Illinois University, Macomb, IL 61455. The heavy and light hole transitions of an MBE (Molecular-Beam-Epitaxy) grown Al (0.3) Ga (0.7) As / GaAs MQW (Multiple Quantum Well) sample were investigated over a temperature range of 20-300 K using the technique of photoluminescence. The MQW sample contained GaAs wells of widths 47 Å, 70 Å, 93 Å, 117 Å and 140 Å sandwiched between AlGaAs barriers of >500 Å. Because the bandgap of GaAs (1.4 eV) is less than that of the AlGaAs (1.8 eV), the electron-hole recombinations take place almost entirely within the one-dimensional quantum wells formed by the narrow layers of GaAs. The MQW sample was illuminated with the 4880 Å line of an Argon-Ion Laser with an incident power at the sample surface of approximately 20mW. The sample was mounted on a cold head and its temperature controlled with a closed-cycle Leybold helium refrigeration system and monitored by a Lakeshore platinum resistor. The photoluminescence spectra were collected using an automated single grating (1200 grooves/mm) Triax 550 spectrometer equipped with a GaAs PMT (photo-multiplier tube) and controlled with LabView data acquisition software. The temperature dependence of all transition energies were found to closely follow the conventional GaAs empirical equation for temperature dependence. In addition, the transition energies appropriately scaled as the inverse square of the well-width, as predicted from one-dimensional quantum mechanical theory, except for slight departure at very narrow well widths.
Raman and EXAFS Studies of Low-Ni-Doped YBCO Superconductors . Michael C. Baxa, No Soung Myoung, and Mark S. Boley, Western Illinois University, Macomb, IL 61455. Raman spectroscopy studies were conducted on YBa2Cu3O7-d samples doped with molar-proportional percentages (0.1%, 0.2%, and 0.3%) of Ni (Nickel) replacing the Cu (Copper) in the starting materials, along with a control sample of pure YBCO, using the 5145 Å line of an Argon-Ion Laser with an incident power at the sample surface of approximately 150mW. The sample was mounted on a cold head and its temperature maintained at 20K with a closed-cycle Leybold helium refrigeration system and monitored by a carbon-glass resistor. The Raman spectra were collected using an automated single grating (1200 grooves/mm) Triax 550 spectrometer equipped with a GaAs PMT (photo-multiplier tube) and a holographic Super-Notch Plus filter and controlled with LabView data acquisition software, also allowing for the average of data collected over multiple scans. The spectral peaks that were monitored correlated with oscillation modes of the yttrium, copper, barium, and oxygen atoms within the unit cell, and did not show noticeable differences within the range of error across the samples. Extended X-ray absorption fine structure (EXAFS) studies were previously conducted on these samples, using the Advanced Photon Source at Argonne National Laboratory, to determine what changes had been produced in the local atomic structure. Both the EXAFS and the RAMAN studies lead us to believe that the optimized transport critical current density observed in the 0.2% Ni-doped sample does not result from differences in local atomic structure, but is most likely produced by grain boundary contamination.
New Innovations in Introductory University Physics. Kevin R. Kimberlin, Conley Stutz, Kelly R. Roos, Douglas Early, Bradley University, Peoria, IL 61625. A fundamental change in laboratory design is needed at the introductory level at Bradley, prompted by a lack of interest in laboratories, partly due to a bureaucratic formal write-up process. A new series of paperless laboratories based upon directed inquiry in an effort to familiarize the student with laboratory equipment and fundamental concepts has been developed at the calculus-based introductory level. As an evaluation of competency and independent study after a number of these labs, the student is then expected to use the skills learned to design an experiment to test the validity of Conservation of Energy in two lab periods once each week for two weeks. The three major parts are proposal discussion by group presentation, collection and analysis of data, and the final report in publication style. Success and pitfalls of the student designed labs will be discussed.
Design and Construction of a 1.5 Mev Cyclotron. Jeffrey Smith and Andrew McDowell, Knox College, Galesburg, IL 61401. A 1.5 Mev cyclotron has been designed and constructed for use in a 2 tesla NMR magnet as part of a senior honors project. The machine is designed to accelerate protons and extract the beam into a bombardment chamber. The basic physics of the cyclotron plus various aspects of its components (vacuum chamber, magnet, dees, RF power supply, dee driver, ion source and beam extraction system) and its design and construction will be discussed.
Papers to be Presented on Saturday Morning
Surface Plasmon Resonance in Thin Ag films. Trisha Hinners, Southern Illinois University Edwardsville, Edwardsville, IL 62025. My research involves the optical excitation of plasmons in approximately 550 Angstrom thick silver films, vacuum deposited onto the planar surface of a semi-cylindrical quartz substrate. A plasmon is the collective oscillation of the free-electrons in a metal. They can be excited by passing a charged particle near the metal or by optical coupling to an incident photon. The goal of this research was to measure the intensity of plasmon radiative decay from thin silver films as a function of the age of the silver surface during exposure to ambient atmosphere.
The Patience of Building a Classical Cassegrain. Anne Wake and Art Braundmeier, Southern Illinois University Edwardsville, Edwardsville, IL 62025. A senior assignment is required of all students at Southern Illinois University Edwardsville. A senior assignment is a capstone experience meant to demonstrate that the student has achieved mastery of a specific topic in their major. An example of a capstone project that meets these criteria is the self-directed construction of a Cassegrain telescope. Constructing a telescope requires a firm grasp of real-world optics, celestial mechanics, and machinery skills. This talk will highlight the trials and tribulations of this project.A Mobile Holography Lab. Laurie Pichla and James Rabchuk, Western Illinois University, Macomb, IL 61455. The advent of cheap and easily accessible laser diodes has fueled a renewed interest in doing holography in the classroom. Several Internet sites describe holography setups which cost around one-hundred dollars, and produce holograms of remarkably good quality. We have incorporated laser diode holography as part of an outreach program conducted by the Western Illinois University departments of Physics and Chemistry and funded by the Illinois State Board of Education. In this talk we will describe the specifics of the holography setup, problems that we have encountered, and the overall success of the activity. We have found that laser diode holography is an exciting and motivating opportunity to introduce the study of light into the elementary and high school classroom.
Changing My Syllabus to Change Student Attitudes and Behavior. Bill Hogan, Joliet Junior College, Joliet, IL 60431. I was frustrated with the approach many of my students took to my introductory physics courses until I realized that I was inadvertently encouraging students to take this approach I disliked so much. I also was disturbed by the fact some students passed my course when I felt they understood very little about the material because they did so well on parts of the course others could help them with. I have completely overhauled my syllabus over the last few years and I am pleased with the results. I will discuss the changes I have made and the changes I see in the approach my students take.
Building a Physics Presence. Gwen Pollock, Illinois State Board of Education N-2443 , Springfield, IL 62777 . Illinois has recently received a special contract from the National Science Teachers Association for its Building a Presence program. We need to be able to have a point of contact in every school in the state and encourage the recruitment of key leaders. This networking potential could be wonderfully filled by physics education leaders throughout the state. The overview of the program and instructions for becoming a part of the network will be provided.
Either Day Will be Fine
LabVIEW as an Educational Tool at Principia College. B. Brown, D. Cornell, P. Robinson, Principia College, Elsah, IL 62028. Skill in solving instrumentation and control problems using LabVIEW is a saleable skill in today's market, and we feel it also offers a logical progression for small schools without a large engineering department to provide both engineering and research training for undergraduates. We are currently introducing LabVIEW in the beginning physics courses and find it very useful in the advanced laboratory course and for senior research projects.
DC Circuits Revisited. Ann Brandon and Deborah Lojkutz, Joliet West High School, Joliet, IL 60435. We have been refining our unit on DC Circuits. We will present our "current" setup, labs, homework, and rationale as well as recent results.
The Basics of Twisted Nematic Liquid Crystal Displays (TN-LCD). Renata Marroum, Benedictine University, Lisle, IL 60532. A hands-on classroom model to explain the basics principles behind Twisted Nematic Liquid Crystal Display (TN-LCD) will be presented. A simple TN-LCD consists of two pieces of glass filled with an eutectic thermotropic nematic liquid crystal mixture. The insides of the glass surfaces are coated with Indium Tin Oxide, a transparent conducting material, and are treated with a polyimide. They are then rubbed in a perpendicular direction so that the liquid crystal molecules align in a 90º twist. The glass substrates are separated with a spacer that is a few microns thick to keep the liquid crystal from being squeezed out of the cell. The cell is sandwiched between two crossed polarizers. In the OFF state, the liquid crystal molecules rotate the plane of polarization, and the cell is clear. Since liquid crystal molecules are sensitive to external perturbations, when an electric field is applied, (ON state), the 90º twist is distorted, thereby blocking the light and creating a black cell. Sample TN-LCD will be given to participants for use in the classroom.
Teaching Introductory Physics in the SCALE-UP Mode, a New Paradigm for Bradley University. Conley Stutz, Kevin Kimberlin, Kelly Roos, Bradley University, Peoria, IL 61625. The methodology used by Robert Beichner at North Carolina State in his SCALE-UP introductory physics courses is being adapted to the teaching of these courses and others at Bradley University. We will be showing the physical layout of the renovated space and how we have adapted this space for teaching the introductory courses in a variety of formats. We will show how the space is laid out so that it can be use in the traditional laboratory mode, the lecture mode, the "directed inquiry" mode, or in the "interactive" activity based mode.
A Mobile Physics Laboratory for the Elementary Science Classroom. Jason Mattis, Dr. James Rabchuk, Western Illinois University, Macomb, IL 61455. A Mobile Physics Laboratory for the Elementary Science Classroom The Physics and Chemistry Departments of Western Illinois University have been funded by the ISBE to develop a Pilot Program for changing attitudes towards science and promoting scientific literacy among K-12 students of rural, west central Illinois. The second phase of our outreach has been to develop laboratory modules that can be transported to the local schools and conducted in the classrooms. The Physics department has developed three such mobile laboratories, covering the topics of Graphing and Motion, Sound and Waves, and Light and Holography. For the Graphing and Sound labs, activities were developed using Vernier LabPro® interfaces and sensors. The interfaces and sensors are used by the students for one of the various activities, and then brought to the supervisor for viewing and comment before the whole group, using a USB connection to a portable laptop hooked up to a portable projector. The advanced technology allows students to do hands-on activities and then view the associated graphs that illustrate the related key concepts. We will describe the set up, the concepts that are taught, and our experiences in the field in 4th and 6th grade classrooms.
Initiation of Surface Science Research at Bradley University. James Craig, Kelly Roos, Kevin Kimberlin, Brian Davies, Bradley University, Peoria, IL 61625. Experimental surface science offers a variety of learning opportunities for undergraduate students at various levels. We describe recent equipment acquisitions by Bradley University and the ways we involve students in original research in two focus areas: the growth of Ag and Si overlayers on silicon surfaces, and the adsorption of NO on germanium surfaces.
Cosmic Ray Detectors in High Schools. Julie Breden, Justin Huebener, David E. Kraus, and Julia A. Thompson, Southwestern High School and SIUE, Piasa, IL . During the past year, exploratory activities have been carried out with the first year physics class of Ms. Julie Breden at Southwestern High School, aimed at familiarizing students with some simple particle detectors, acquainting them with the connection between cosmic rays seen at the surface of the earth, the high energy particles entering the earth's atmosphere, and the possible sources for such high energy particles. One goal is to assess the potential success of such studies for enhancing student interest in physics and astrophysics while imparting some information about particle detection and associated electronics and other technical topics. The national context of this idea as well as our local experience will be discussed.
Newly Registered Papers