Eric Sembrat's Test Bonanza

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Supermassive black holes suck in surrounding materials

Thursday, April 14, 2011

Assistant Professor David Ballantyne and his co-authors, J.R. McDuffie (Center for Relativistic Astrophysics) and J.S. Rusin (South Cobb High School student) published an article entitled:  “A Correlation Between the Ionization State of the Inner Accretion Disk and the Eddington Ratio of Active Galactic Nuclei” in The Astrophysical Journal.  The paper addressed supermassive black holes in the centers of galaxies grow by ‘accretion’ -- that is, they suck in material from their surroundings which swirls into the black hole like water going down the drain. Now, the actual physics involved in how an accretion disk works is complicated, and, because these accreting black holes are so very far away, it is very difficult to test accretion disk theories by observations with telescopes. However, these accretion disks get so hot as they swirl around the black hole that they produce X-rays and these X-rays interact with the accreting gas leaving ‘fingerprints’ of accretion physics in the X-ray radiation that astronomers can detect. This paper uses these fingerprints from a number of different accreting black holes and describes the discovery of a relationship between the ionization state of the accreting gas close to a black hole and how rapidly the black hole is being fed. Basically, we see that the more rapidly a black hole is gobbling material, the more highly ionized its accretion disk. The exact implication of this relationship is unclear, but further study will allow new tests of our theories of how black holes grow in the universe.

Summary: 

Supermassive black holes suck in surrounding materials

Intro: 

Supermassive black holes suck in surrounding materials

Alumni: 

Scientists Finely Control Methane Combustion to Get Different Products

Thursday, April 14, 2011

Scientists have discovered a method to control the gas-phase
selective catalytic combustion of methane, so finely that if done at room
temperature the reaction produces ethylene, while at lower temperatures it
yields formaldehyde. The process involves using gold dimer cations as catalysts
— that is, positively charged diatomic gold clusters. Being able to catalyze
these reactions, at or below room temperature, 
may lead to significant cost savings in the synthesis of plastics,
synthetic fuels and other  materials. The
research was conducted by scientists at the Georgia Institute of Technology and
the University of Ulm. It appears in the April 14, 2011, edition of The Journal of Physical Chemistry C.

“­The beauty of this process is that it allows us
to selectively control the products of this catalytic system, so that if one
wishes to create formaldehyde, and potentially methyl alcohol, one burns
methane by tuning its reaction with oxygen to run at  lower temperatures, but if it’s ethylene  one is after, 
the reaction can be tuned to run at room temperature,” said Uzi Landman,
Regents’ and Institute Professor of Physics and director of the Center for
Computational Materials Science at Georgia Tech.

Reporting last year in the journal Angewandte Chemie International Edition, a team that included
theorists Landman and Robert Barnett from Georgia Tech and experimentalists
Thorsten Bernhardt and Sandra Lang from the University of Ulm, found that by using
gold dimer cations as catalysts, they can convert methane into ethylene at room
temperature.

This time around, the team has discovered that, by using the
same gas-phase gold dimer cation catalyst, methane partially combusts to
produce formaldehyde at temperatures below 250 Kelvin or -9 degrees Fahrenheit.
What’s more, in both the room temperature reaction-producing ethylene, and the
formaldehyde generation colder reaction, the gold dimer catalyst is freed at
the end of the reaction, thus enabling the catalytic cycle to repeat again and
again.

The temperature-tuned catalyzed methane partial combustion
process involves activating the methane carbon-to-hydrogen bond to react with
molecular oxygen. In the first step of the reaction process, methane and oxygen
molecules coadsorb on the gold dimer cation at low temperature.  Subsequently, water is released and the
remaining oxygen atom binds with the methane molecule to form formaldehyde. If
done at higher temperatures, the oxygen molecule comes off the gold catalyst,
and the adsorbed methane molecules combine to form ethylene through the
elimination of hydrogen molecules.

In both the current work, as well as in the earlier one,
Bernhardt’s team at Ulm conducted experiments using a radio-frequency trap,
which allows temperature-controlled measurement of the reaction products under
conditions that simulate realistic catalytic reactor environment. Landman’s
team at Georgia Tech performed first-principles quantum mechanical simulations,
which predicted the mechanisms of the catalyzed reactions and allowed a
consistent interpretation of the experimental observations.

In future work, the two research groups plan to explore the
use of multi-functional alloy cluster catalysts in low temperature-controlled
catalytic generation of synthetic fuels and selective partial combustion
reactions.

Media Contact: 

Georgia Tech Media Relations
Laura Diamond
laura.diamond@comm.gatech.edu
404-894-6016
Jason Maderer
maderer@gatech.edu
404-660-2926

Summary: 

Scientists have discovered a method to control
the gas-phase selective catalytic combustion of methane, so finely that if done
at room temperature the reaction produces ethylene, while at lower temperatures
it yields formaldehyde.

Intro: 

Scientists have discovered a method to control
the gas-phase selective catalytic combustion of methane, so finely that if done
at room temperature the reaction produces ethylene, while at lower temperatures
it yields formaldehyde.

Alumni: 

Prof’s Teaching Reaches Students Beyond Tech

Monday, April 4, 2011

Thanks to videoconferencing equipment and a few large-screen televisions, Jennifer Curtis is reaching out to students beyond Tech’s Midtown campus.  

Curtis, an assistant professor in the School of Physics, participates in the Direct to Discovery program, a Georgia Tech Research Institute program that brings research labs into K-12 classrooms with a little help from technology. 

The program’s goal is to help students better understand various areas of science and mathematics in a way that fosters ongoing interest in these areas.   

“Since my lab is so interdisciplinary, we can tie into the curriculum of a physics, chemistry or biology class,” she said. 

According to Kimm Bankston, the Winder-Barrow high school teacher Curtis has worked with, the demos have been quite successful and have stimulated student discussions about science that extend beyond the classroom.

“I think the program is an excellent way to inspire the next generation of engineers and scientists,” Curtis added. 

Recently, The Whistle had an opportunity to learn more about Curtis and her approach to teaching. Here’s what we learned:  

How did you get to Georgia Tech? 

In 2006, both my husband and I were seeking tenure-track academic positions. In the end, it was clear that Tech was the best fit for our combined interests both professionally and personally.

How did you become interested in your area of teaching and research?    

When I started out as an undergraduate at Columbia University, I wanted to pursue photography and writing. But I experienced a major creative block, which led me back to my first love, science and mathematics. The next semester, I started taking physics classes and the rest is history. As for becoming a biophysicist, I always loved biology and after observing that some of the most interesting work done by physicists was in the area of biophysics, I knew where I needed to be.    

In a few sentences, tell us a little bit about your research focus.

My research group studies the mechanics of cells and biomaterials. Also, we invent or develop unique tools to help answer questions about, for example, the coating of a  cell.       

What is your greatest challenge as an instructor, and how have you dealt with it? 

Helping students figure out how to learn and study effectively is always a challenge. For example, there is always a large group of students who work very hard and spend vast amounts of time studying for my introductory physics course. Yet, their performance on tests does not reflect their efforts. I am experimenting with how to instruct students to get to the point where they can internalize and comprehend the difference between deeply understanding how and why they solve problems a certain way versus superficially memorizing or accepting a concept or problem-solving strategy in physics.  

What piece of technology could you not live without as an instructor?

I think a tablet PC works wonders for large classroom lecture halls.   

Where is the best place to grab lunch and what do you order? 

My favorite place used to be Bobby and June’s, but it recently closed. I’d order the Salisbury steak with a side or two of vegetables.

Tell me something unusual about yourself. 

When I was younger, I was a competitive épée fencer and trained several hours a day while I was in high school and for part of my time in college.

Media Contact: 

Amelia Pavlik
Communications & Marketing
404-385-4142 

Summary: 

Thanks to videoconferencing equipment and a few large-screen televisions, Jennifer Curtis is reaching out to students beyond Tech’s Midtown campus.

Intro: 

Thanks to videoconferencing equipment and a few large-screen televisions, Jennifer Curtis is reaching out to students beyond Tech’s Midtown campus.

Alumni: 

Physics Undergraduate Student Awarded NSF Graduate Research Fellowship

Thursday, April 7, 2011

Physics undergraduate student Holly Tinkey has been awarded an NSF Graduate Research Fellowship for her proposal on "Metal Halide intercalation of multi-layered graphene films".

The NSF Graduate Research Fellowship Program (GRFP) recognizes and supports outstanding students who are pursuing research-based master's and doctoral degrees in fields within NSF's mission. The GRFP provides three years of support for the graduate education of individuals who have demonstrated their potential for significant achievements in science and engineering research.

Summary: 

Physics undergraduate student Holly Tinkey has been awarded an NSF Graduate Research Fellowship.

Intro: 

Physics undergraduate student Holly Tinkey has been awarded an NSF Graduate Research Fellowship.

Alumni: 

Professor Jennifer Curtis Teaches Students Beyond Tech

Monday, April 4, 2011

Assistant Professor Jennifer Curtis was featured in The Whistle.

Summary: 

Thanks to videoconferencing equipment and a few large-screen televisions, Jennifer Curtis is reaching out to students beyond Tech’s Midtown campus.

Intro: 

Thanks to videoconferencing equipment and a few large-screen televisions, Jennifer Curtis is reaching out to students beyond Tech’s Midtown campus.

Alumni: 

Physics Graduate Student Research Presented at GTRI Shackelford Showcase

Tuesday, April 5, 2011

Grahame Vittorini was one of 12 graduate students selected to present a poster of his research at the third annual GTRI Shackelford Showcase.  His presentation was titled “Efficient Sympathetic Cooling of Trapped Ions in Planar Ion Traps.”

The Shackelford Graduate Fellows Program is designed to provide an environment for graduate level research while providing financial support to qualified graduate students. The program also provides another avenue for academic collaboration between the research units at GTRI and various academic units through joint direction and supervision of graduate student research.

The program honors the service and personal integrity which Robert Shackelford brought to GTRI during his 34-year career at Georgia Tech.

Summary: 

Grahame Vittorini was one of 12 graduate students selected to present a poster of his research at the third annual GTRI Shackelford Showcase. His presentation was titled “Efficient Sympathetic Cooling of Trapped Ions in Planar Ion Traps.”

Intro: 

Grahame Vittorini was one of 12 graduate students selected to present a poster of his research at the third annual GTRI Shackelford Showcase. His presentation was titled “Efficient Sympathetic Cooling of Trapped Ions in Planar Ion Traps.”

Alumni: 

School Chairs Honored at College of Sciences Reception

Monday, April 4, 2011

On March 29, the College of Sciences hosted a reception in honor of Prof. Mei-Yin Chou's service as School Chair and welcoming Prof. Paul Goldbart as he takes on the role of Chair.

To view all the photos, go to this link.

Summary: 

On March 29, the College of Sciences hosted a reception in honor of Prof. Mei-Yin Chou's service as School Chair and welcoming Prof. Paul Goldbart as he takes on the role of Chair.

Intro: 

On March 29, the College of Sciences hosted a reception in honor of Prof. Mei-Yin Chou's service as School Chair and welcoming Prof. Paul Goldbart as he takes on the role of Chair.

Alumni: 

School of Physics Faculty Promoted

Thursday, March 31, 2011

Deirdre Shoemaker has been granted a promotion at Georgia Tech, to the rank of Associate Professor.  

Deirdre Shoemaker came to Georgia Tech in 2008 as a founding member of the Center for Relativistic Astrophysics.  Earlier, she had been an assistant professor at Pennsylvania State University, where she had been a postdoctoral researcher, following her 1999 Ph.D. from the University of Texas, Austin.  She is a theorist who solves the equations of general relativity numerically -- work that is timely and potentially very influential, as it is widely anticipated that gravitational waves from black holes and neutron stars will be observable in the near future.  Deirdre’s group is one of the leading teams both for modeling the events that produce gravity waves and for analyzing the data encoded in those waves.  Her accomplishments and promise have been recognized with a National Science Foundation CAREER award.  

Summary: 

Deirdre Shoemaker has been granted a promotion at Georgia Tech, to the rank of Associate Professor.

Intro: 

Deirdre Shoemaker has been granted a promotion at Georgia Tech, to the rank of Associate Professor.

Alumni: 

COPE Award to Keith Carroll

Tuesday, March 1, 2011

The Georgia Tech Center for Organic Photonics and Electronics (COPE) is a premier national research and educational resource center that creates flexible organic photonic and electronic materials and devices that serve the information technology, telecommunications, energy, and defense sectors.  In 2011, Physics graduate student Keith Carroll received a COPE award. Keith is a graduate student in Professor Jennifer Curtis's lab , and collaborates with Profs. Elisa Riedo's and Seth Marder's labs.

COPE creates the opportunity for disruptive technologies by developing new materials with emergent properties and by providing new paradigms for device design and fabrication.  Keith’s research focuses on the development and applications of thermochemical nanolithography.  The aim is to improve current capabilities with respect to resolution, speed, and versatility.  The ultimate intent is to open the technique to a number of applications ranging from biophysics to electronics.

COPE Awards help enable a new generation of devices and systems that meet the challenges that these sectors and our ever-changing society face in this decade and the future.

Summary: 

Physics graduate student Keith Carroll receives COPE award.

Intro: 

Physics graduate student Keith Carroll receives COPE award.

Alumni: 

Georgia Tech Faculty Takes Three Sloan Fellowships

Friday, February 18, 2011

Three faculty members from
the Georgia Institute of Technology were awarded 2011 Sloan Research
Fellowships by the Alfred P. Sloan Foundation. Christopher J. Peikert, from the
College of Computing, along with Silas D. Alben and Shina Tan in the College of
Sciences, were three of 118 outstanding researchers selected from across the
country. They were the only recipients of the award from the state of Georgia. Awarded
annually since 1955, the fellowships are given to early-career scientists and
scholars in recognition of achievement and the potential to contribute
substantially to their fields.

Drawn from 54 colleges and
universities in the U.S. and Canada, this year’s fellows represent an
extraordinarily
broad range of research interests, including an astronomer who studies the
birth of new planets, a computer scientist who examines how changes in computer
network architecture can save energy, an economist who investigates the
game-theoretical foundations of cooperation, and a
mathematician
who uses geometry to model how the brain represents stimuli.

“The scientists and
researchers selected for this year’s Sloan Research Fellowships represent the
very brightest rising stars of this generation of scholars,” says Paul
L. Joskow, president of the Alfred P. Sloan Foundation. “The
Foundation is proud to be able to support their work at this important stage in
their careers.”

Silas
Alben, an assistant professor in the School of Mathematics, studies how fluids
flow and exert forces on flexible solid bodies. His research is designed to enhance
understanding of how fish swim in an effort to guide the design of swimming
robots.  He also investigates how thin
solid plates can deform to create novel three-dimensional structures.

Shina
Tan, an assistant professor in the School of Physics, studies the theory of
dilute cold matter, which is millions of times thinner than the air and
billions of times colder than an average home freezer. His research may have
applications to sensitive detection and precision measurements.

Christopher
Peikert, assistant professor in the School of Computer Science, focuses on
geometric “lattices” as a new mathematical foundation for cryptography (the
science of developing secret codes and the use of those codes in an encryption
system). In principle, quantum computers could break much of the cryptography
in wide use today, so there is a strong need for alternative schemes. The
lattice approach yields very simple schemes that are highly efficient and
parallelizable.

Administered and funded by
the Sloan Foundation, the fellowships are awarded in close cooperation
with the
scientific community. Potential fellows must be nominated for recognition by
their peers and are subsequently selected by an independent panel of senior
scholars.

The $50,000 fellowships are
awarded in chemistry, computer science, economics, mathematics,
evolutionary and
computational molecular biology, neuroscience and physics. In 2012, in
recognition of the important work done by Sloan-sponsored researchers working
on the Census of Marine Life, the award program will be
expanded to include fellowships in ocean sciences.

For a complete list of
winners, visit: www.sloan.org/fellowships/page/21

Adapted from a release by the
Alfred P. Sloan Foundation

The Alfred P. Sloan
Foundation
is
a philanthropic, not-for-profit grant making institution based in
New York City.
Established in 1934 by Alfred Pritchard Sloan Jr., then-president and chief executive
officer of the
General Motors Corporation, the Foundation makes grants in support of original
research and
education in science, technology, engineering, mathematics and economic
performance. www.sloan.org.

Media Contact: 

Georgia Tech Media Relations
Laura Diamond
laura.diamond@comm.gatech.edu
404-894-6016
Jason Maderer
maderer@gatech.edu
404-660-2926

Summary: 

Faculty from the Colleges of
Sciences and Computing are honored as outstanding researchers.

Intro: 

Faculty from the Colleges of
Sciences and Computing are honored as outstanding researchers.

Alumni: 

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