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.
Observing growth processes in classical alloys is extremely difficult; scientists overcame this by studying quantum systems.
Scientists are welcoming a new MRI machine at the National MagLab that provides the best spatial resolution available for human imaging, making it a powerful tool for nationwide, multi-site health research.
Manufactured by Siemens, the state-of-the-art, whole-body scanner is powered by a 3-tesla magnet (tesla is a unit of magnetic field strength). But it's not the machine’s main magnetic field — on a par with many hospital MRIs — that makes the instrument special. Rather, the unit features the most powerful gradient magnet fields available, which help generate very sharp images of very tiny anatomical structures.
“Gradients provide the high spatial resolution in MRI, and with the new system we get the localization we need for small structures,” said Joanna Long, director of the MagLab's Advanced Magnetic Resonance Imaging and Spectroscopy (AMRIS) facility at the University of Florida, where the new instrument is located.
For anyone who has been inside an MRI machine, the gradient magnetic fields are responsible for that unpleasant racket you hear; technicians trigger them to target different areas of the body. But they also help generate more precise images – in this case, around a millimeter in resolution, allowing scientists to see bundles of neurons inside the brain. (Learn more about how MRI machines work).
As one of a number of similar machines recently installed around the country, the new system will enable researchers working at AMRIS to participate in large-scale, multi-site health studies. For example, some AMRIS researchers are using the machine as part of a years-long study to track brain cognitive development in adolescents. Others will use it for research on Alzheimer’s and Parkinson’s disorders. Glenn Walter, an associate professor in physiology and functional genomics at the University of Florida, is using it to develop MRI techniques to assess how effective drugs are at treating muscular dystrophy, a less invasive approach than muscle biopsy.
By allowing MagLab users to participate in such longitudinal studies, the $3 million system will yield high research dividends. “It's a really good example of how the magnetic resonance research program at the MagLab can leverage something bigger,” Long said.
To celebrate a trio of recent upgrades, including the new MRI machine, added dynamic nuclear polarization capabilities, and a new console for the 11-tesla MRI/S system, AMRIS hosted a reception and symposium this week.
Text by Kristen Coyne; Image courtesy of AMRIS.
Scientists using an MRI-friendly oxygen isotope have demonstrated a promising and safe method for identifying cancerous tumors.
Combining tremendous strength with a high-quality field, the MagLab’s newest instrument promises big advances in interdisciplinary research.
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, 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.
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.
This week at the lab, a prosaic-looking box is being prepared to assume a very exciting job this summer as a key component to a scientific time machine.
Although researchers won't be able to use the approximately 4-foot-high box to travel to other eras, they will use it to get a tantalizing glimpse of science in the future.
Delivered to the lab last week from Switzerland, the "box" is in fact a one-of-a-kind console specifically designed and built by Bruker Corp. for a new, one-of-a-kind instrument, the MagLab's 36 tesla series connected hybrid (SCH) magnet. Due to come online in a few months, the SCH will offer the highest magnetic fields in the world for nuclear magnetic resonance (NMR) research. With an operating frequency of 1.5 gigahertz, it will be one and a half times stronger than any other NMR magnet, said Ilya Litvak, who is coordinating the NMR instrumentation for the new magnet.
The MagLab already has numerous magnets for NMR, used to study the structure of molecules by interacting with the nuclei of atoms such as hydrogen, nitrogen and carbon. What's special about the new magnet is that, operating at 1.5 gigahertz, it will allow scientists to efficiently target so-called "low-gamma" nuclei such as oxygen, which are too hard to see at conventional NMR field strengths, opening up a whole new frontier for scientific exploration.
"In the two areas where structure is important, biological research and materials, you have a lot of oxygen," said Litvak. "Currently, scientists cannot use oxygen in NMR efficiently."
A Bruker engineer is testing the new console with another magnet while construction on the SCH magnet is completed. In NMR experiments, the console receives and records the signals sent to it by the probe, which holds the sample inside the magnet.
Text by Kristen Coyne, photo by Stephen Bilenky.
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