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Student/Faculty Collaborative Research
Projects
The National Conference On Undergraduate Research (NCUR) 2008 Salisbury University, Salisbury, Maryland April 10-12, 2008 The production of Si from SiO2 via the
Ball-Milling Technique Margaret Samuels Department of Physics Goucher College 1021 Dulaney Valley Road Baltimore, MD 21204 Faculty Advisor: Dr. Ali Bakhshai Abstract The ball milling technique employs mechanical energy
to reduce the particle size of reactants to a size small enough to cause
defects in their lattice structures.
In exothermic reactions, self-heat propagating synthesis (SHS) has
been known to occur, allowing a complete reaction via mechanical energy. However, extracting silicon from silicon
oxide using aluminum is endothermic, and therefore, milling does not complete
the reaction. This study sought to
supplement the lattice defects with energy supplied by moderate heat
treatment as a method of producing pure silicon. The parameters tested were annealing
temperature, milling time, and annealing time. The relationship between annealing temperature
and milling time was also investigated thoroughly. X-ray diffraction, as well as some
comparison with Atomic Force Microscopy, was used to determine the presence
of products in samples. The data
confirmed that milling is necessary for the reaction to take place, and that
even one minute of milling can change the products significantly. The use of milling, combined with a
moderate heat treatment, can produce silicon in a way that is more
environmentally friendly than current methods, more cost-effective, and can
be used at tonnage proportions for industrial purposes. Keywords:
ball-milling technique, silicon oxide, aluminum, mechanical energy, moderate
heat treatment
Proceedings of The National Conference On Undergraduate Research (NCUR) 2007, Dominican University of California, San Rafael, California, April 12-14, 2007. Anomalous Reaction of Silicon Oxide and Aluminum via Ball Milling, M. Marx, R. M. Kolagani*, G. Young*, Aghasi Torsyan+, and A. Bakhshai Department of Physics, Goucher College, 1021 Dulaney Valley Road, Baltimore, MD 21204, USA, * Towson University, Towson, MD 21252, +Institute of General and Inorganic Chemistry, Yerevan, Armenia Abstract Previous studies have shown that the ball milling
technique, which mechanically imparts energy to the reactants, often causes a
displacement reaction between various metals and metal oxides. Usually ball milling causes a self-propagating
heat synthesis reaction (SHS) to occur with exothermic reactions. This study was undertaken to see whether
the ball milling technique could provide a method to extract pure silicon
from silicon oxide. Since silicon
oxide and aluminum are readily available materials, the ball milling process
would be an easy and cost efficient way to produce silicon. The parameters tested in this study
included varying the amount of aluminum, total powder mass, number of balls
(kinetic energy), and milling atmosphere.
Parameters also tested were additions of acetone and alcohol. X-ray diffraction was used to determine
what elements and compounds were present before and after ignition. This study discovered that when silicon
oxide and aluminum were milled SHS does not occur despite the reaction being highly
exothermic. Keywords: mechanical alloying, ball milling
technique, self-propagating heat synthesis, silicon oxide, aluminum
Proceedings of The
National Conference On Undergraduate
Research (NCUR) 2006 University of North
Carolina Ashville Ashville, North
Carolina April 6-8, 2006 Nano-Composites
and Mechanical Alloying Via the Ball Milling Technique J. Sergeant
and A. Bakhshai Department of
Physics Goucher
College 1021 Dulaney
Valley Road Baltimore, MD
21204, USA Abstract Ball
milling technique has been utilized to produce nano-composites and to
ascertain the fundamental parameters of the mechanochemical reaction and the
mechanical alloying process. This is an innovative method of material
synthesis that, compared to the current methods, is very cost effective and
environmental friendly although it has not been
thoroughly analyzed. There are some general understandings of
mechanical alloying based on the basic thermodynamics of the reaction that
have been widely accepted. Certain parameters of these theories have
been investigated and confirmed through experimental data. These
fundamental parameters help the understanding of the ball milling process. Keywords: Mechanical alloying, ball milling,
nano-composites Click Here for PowerPoint Presentation of John Sergeant
Proceedings of
the National Conference Washington and
Lee University Virginia Military
Institute Lexington, Virginia Rotational Curve and
Gravitational Mass of Galactic Interior at 21-cm Hydrogen Line Observance J. Zeck and A. Bakhshai Department of Physics and Astronomy Goucher College 1021 Dulaney Valley Road Baltimore, MD 21204. USA Faculty Advisor: Dr. Ali Bakhshai Abstract A Small Radio Telescope (SRT) was installed and calibrated to allow
for interstellar hydrogen spectral readings at 1420 megahertz frequency.
Observance of the 21-cm Hydrogen Line produced in accordance with this
frequency allowed for a determination of the rotational velocity of the
galaxy within the 8.5kpc region between the Sun and the center of the galaxy.
Plotting rotational velocities as a function of galactic radius yielded a
galactic rotation curve that approximately models the rotational behavior of
the galaxy from the solar system to the galactic center. The rotational curve
observed is relatively constant and thus characteristic of a system that has
uniformly distributed mass. Stars and other known celestial masses are too
few and scattered to account for such an observed distribution, thus
assertions about the presence of interstellar ‘dark matter’ are justifiable.
Rotational velocity values were also utilized to approximate the
gravitational mass of the galaxy’s interior. Student Author: Jay Zeck (Class of
2005)
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