Sylke Boyd, PhD
Current Courses: (Fall 2013)
Office hours for Fall 2013: Monday 11:00 am to noon; Tuesday 1:00-2:00 pm; Friday noon to 1:00 pm , and with arrangement (check my Google calendar for options)
Courses taught recently:
Phys1101 General Physics 1 (Spring 2013) , Phys3501 Statistical Physics (Spring 2013), (Phys1063 Physics of Weather (F2012), Phys3003 Computer Modeling of Materials F2012,(Classical Mechanics (Fall 2010), Computer Modeling of Materials (Fall 2012), FYS Bottomdwellers in an ocean of air (fall 2006), Physics of Sound and Music (fall 2005)
Courses that may never come to pass:
This course would take us to Freiberg, Sachsen, Germany. We would explore a beautiful gentle mountain range with an 800-year history of mining.
Student Research Projects:
James Froberg ’14 Development of a ray tracing program for halo simulations in Matlab
Stephen Sorensen’14 Halo observations with the All-sky camera
Zach Klassen’14 and Josef Wieber’14 Climate variability and land use – and analysis of long-term weather records in the upper Midwest
Robert Smith’13 RDX elastic constants in RDX and the influence of voids on the elasticity tensor
Chad Reverman’13 Bulk modulus of RDX and the influence of voids
Matthew Kroonblawd’12 Energy distribution in RDX during shock
Jerry Kessler’11 Statistical analysis of 90-year longitudinal weather record in Morris
Johanna Martin’10 Water droplet formation in clouds (MAP 2008/9)
Anna Schliep’07 Dislocations in RDX (GIA, URS 2007 poster)
Sound generation by wind in Strings (UROP, finished, presented as poster at MAAPT Fall 2006 meeting, URS 2007 poster)
Sam Geller’07 Monte Carlo Simulations of Vacancies in a Crystal (GIA, active, presented as poster at MAAPT Fall 2006 meeting)
Matt Gravelle ‘05 Point defects in RDX (UROP and GIA, finished, presented posters at URS and CCTCC, coauthor of publication)
If you are interested in any way to collaborate in a research project please do not hesitate to stop by or drop a line by e-mail.
In recent years, my interest has shifted toward atmospheric physics. Droplet formation, cloud formation, ice crystal growth, the use of optical phenomena to observe and measure aerosols, in particular droplets and ice crystals are at the center.
During the past decade, my research interest has been in computer simulations of materials, including force field development, molecular dynamics and Monte Carlo simulations. Materials modeling allows to address questions that are either hard to access experimentally, or for which experimental results are in need of explanation. To some degree, reliable models can have predictive power, but also provide insight into the mechanisms of otherwise inaccessible phenomena. A successful computer model for a materials problem rests is based on three elements:
Left to right: 22°Halo and parhelia; 22° and 46° halos, parhelia and upper-tangent arc; sun pillar and a Parry arc; Light pillars above campus; 22° halo in cirrus(photos by S. Boyd); ray tracing in a hexagonal platelet (James Froberg, MATLAB)
These optical phenomena are caused by refraction and reflection in ice crystals that form in the air. Ice crystals may form as hexagonal platelets, columns, pencils, needles, hollow columns and a wide variety of combination forms. Their shapes are related to temperature and supersaturation conditions in their local environment. Observing and interpreting Halo phenomena can give us information about atmospheric conditions in elevated layers without direct probing. This project addresses two questions: (1) How frequent are halo phenomena, and which kinds are observed in our local area? (2) Which ice crystal shapes would favor particular halo appearances in the sky? Such observations and studies are performed throughout locations all over the world, as a means of passive remote sensing, and a pathway to understand cloud composition as it relates to the origin of the clouds. Stephen Sorensen has been working on controls for the allsky fisheye camera (installed by physics professor Gordon McIntosh and his students for meteor observations) to allow recording images of sky conditions throughout the daylight hours. He will work on the development of an image-processing program to recognize and categorize various halo appearances. James Froberg has developed a MATLAB program that runs statistics on optical rays through ice crystals and provides an angular distribution of the exiting intensity. He will expand this program to 3d ice crystals and to allow for variation in orientation of the crystals through the academic year 13/14.
2. Weather and climate: I am interested in using long-term weather records to assess local climate variability. After Jerry Kessler’s analysis of a 90-year temperature record taken in Morris MN (2010) it appeared that the minimum temperatures have increased dramatically throughout the record period, while other climate markers were variable and showed no significant trends. Results of the analysis are given here. One could speculate about an increase of water vapor due to an intensification of agriculture throughout the period. The data only included monthly mins, maxes and averages, and were limited to 90 years. During summer of 2013, Zachary Klassen and Josef Wieber conducted an extensive study on twelve locations throughout the Midwest, using daily data and up to 130 years of record-keeping. It is a search process for possible correlations in land-use and variations in climate markers. It appears that the increase in minimum temperatures is a trend observed in all land forms.
Maps of the trends in February minimum temperatures, the August daily temperature range and the January mean temperature. Circle size relates to slope (max +-8°C/100yrs); colored = “+”, white = “-“; all plots use the same scale. Winter minum temperatures have increased everywhere. The daily range has decreased in rural areas, and slightly increased in urban areas. The January mean temperatures have small and varied trends.
Animations: NPT simulation of a water droplet of 4000 water molecules at 275 K and 1 atm, water particles shown only.
Recent publications and presentations:
Sylke Boyd, Jane S Murray, and Peter Politzer, Molecular dynamics characterization of void defects in crystalline (1,3,5-trinitro-1,3,5-triazacyclohexane), J. Chem. Phys. 131, 204903 (2009).
Sylke Boyd and Kevin J Boyd, A computational analysis of the interaction of lattice and intramolecular vibrational modes in crystalline alpha-RDX, J. Chem. Phys. 129, 134502 (2008).
Boyd, K. J. Boyd, Vibrational properties of RDX, presented as poster
at the 16th Conference on Current Trends in Computational Chemnistry (CCTCC) in
Boyd, M. Gravelle, Computer Simulations Of Point Defects In Crystalline RDX,
presented as poster at the 2006 Gordon Research Conference on Energetic
Sylke Boyd, Matthew Gravelle, and Peter Politzer, Nonreactive molecular dynamics force field for crystalline hexahydro-1,3,5-trinitro-1,3,5 triazine, , J. Chem. Phys. 124, 104508 (2006).
M. Gravelle, S. Boyd, A computer
study of point defects in the RDX crystal, presented as poster at
the 14th Conference on Current Trends in Computational Chemistry
Super Saturday Science: a science experience for girls 5-8th grade (activity: Air pressure)
Just in case you were wondering what a Nischel is…
Personal stuff – for friends and family
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