Using an advanced technique, scientists discover that one of the most common substances in our everyday lives — glass — is more complex than we thought.
This week at the lab, engineers are fine-tuning a new magnet that will offer scientists a novel way to do nuclear magnetic resonance (NMR).
The magnet, along with a new cabinet and console, comprise the lab’s new 600 MHz spectrometer, which will be used for a new measurement technique with a very long name: magic angle spinning dynamic nuclear polarization. MAS DNP, as it is more reasonably called, gives scientists deciphering the structure of molecules a clearer picture of what they are looking at.
The 2,000-pound Bruker superconducting magnet was installed earlier this month, connected to cryogen and a power supplies, and ramped up to full field, 14.1 teslas. A special feature of the instrument is a second, small, "sweepable" magnet coil that allows scientists to fine-tune the field and frequency of the instrument.
In NMR spectroscopy, scientists put the material they are studying – let’s say a protein – inside the magnet, then direct radio waves of a specific frequency at it. These in turn send back signals identifying certain atoms, thus helping scientists piece together the sample’s structure. In the MAS DNP technique, a solvent containing free radicals is added to the sample. When irradiated with microwaves, the result is much stronger NMR signals and thus a clearer idea of the material’s structure.
This new setup, located in the MagLab’s Nuclear Magnetic Resonance and Magnetic Resonance Imaging / Spectroscopy Facility, is among just a few in the world and the only one open to outside scientists, said Thierry Dubroca, a MagLab physicist who has helped develop the capability. The new system will be available to scientists in early 2016. Scientists interested in using MAS DNP should contact Thierry Dubroca, Zhehong Gan, Ivan Hung, Joanna Long.
Video by Stephen Bilenky / Text by Kristen Coyne
Inspired by the SIM card technology used in modern cell phones, MagLab engineers designed and built a versatile magnet probe that makes it easier and more efficient for scientists to see the structure of molecules.
This week at the lab, scientists from across North America are learning the theory and practice of radio frequency (RF) coils.
RF coils are used in magnetic resonance imaging (MRI) to transmit and receive RF signals. The MagLab’s Advanced Magnetic Resonance Imaging and Spectroscopy (AMRIS) Facility at the University of Florida has an entire lab devoted to RF coil manufacture and development, led by RF engineer Malathy Elumalai.
In response to a growing need for visiting scientists to be able to troubleshoot and design their own RF coils, Elumalai is sharing her expertise at this week’s inaugural coil workshop. Empowering scientists to make their own coils makes sense. The demand for specialized coils has outpaced the rate at which Elumalai can design them. Additionally, sometimes the coils break, causing an experiment to come to a halt.
Throughout this week’s workshop, participants will learn the physics behind RF coils and be trained in specialized software for designing and modeling how the coils will behave under different magnetic fields and with different samples. Participants also have the chance to build their own coil and test it in the MagLab’s 4.7 tesla imaging magnet.
How do RF coils in MRI machines work? First, the coil transmits an RF signal, which produces a magnetic field perpendicular to the one already being produced by the magnet. Then, the same RF coil (or a separate one) receives signals indicating how the nuclear spins inside the subject are relaxing. This information is then processed as an image. Without RF coils, there’d be no "I" (imaging) in MRI!
The workshop is an example of the ongoing training we offer our "users" so that they can make the most of their time with our magnets. The MagLab also offers a User Summer School and a Theory Winter School once a year.
Text and image by Elizabeth Webb.
Observing growth processes in classical alloys is extremely difficult; scientists overcame this by studying quantum systems.
Andreas Neubauer took the extended stay option during his recent trip to the MagLab. After all, you can't rush art — especially when it's mixed with science.
Combining tremendous strength with a high-quality field, the MagLab’s newest instrument promises big advances in interdisciplinary research.
This week at the lab, we’re turning up the heat.
It's summer at MagLab headquarters in Tallahassee, Fla., and the mercury's rising accordingly. But things are really sizzling in our Nuclear Magnetic Resonance and Magnetic Resonance Imaging / Spectroscopy Facility thanks to our new high-temperature laser probe.
At the MagLab, scientists attach the samples they are studying to fancy sticks called probes that they then insert into our powerful magnets. In addition to getting specimens into the magnet, many probes have specific capabilities that allow researchers to get the data they need to answer important scientific questions about materials, energy and life.
The unique capability of the new laser probe is to heat the sample up to a blistering 850 degree Celsius (1,562 degrees Fahrenheit), thanks to a laser beam about a millimeter wide. That alone is pretty cool — errr, hot. But on top of that, it spins the sample around 5,000 times a second, which results in data with much higher resolution data.
The new probe, made by Bruker Biospin Corp., is only the third of its kind in the world, said MagLab chemist Yan-Yan Hu.
"This is the first one in the United States," Hu said. "It's going to be exciting for people to do research that they haven't been able to do before."
Most of those scientists will be doing energy-related research on high-efficiency batteries and fuel cells that operate at intermediate to very high temperatures.
The new probe, to be used with the lab's 500 MHz 89 mm NMR magnet, is a big improvement on previous high-temperature probes, which used gas to heat up the sample. Those probes also had the unwanted consequence of warming up the probe's electronics as well as the magnet.
At the MagLab, we prefer the superconducting magnets to stay pretty cold.
The science, however, is always red hot.
Text and photo by Kristen Coyne.
Producing a high magnetic field that is also very stable and uniform, the unique Series Connected Hybrid magnet is being put to work on NMR experiments never before possible.
Scientists using an MRI-friendly oxygen isotope have demonstrated a promising and safe method for identifying cancerous tumors.