A superconducting magnet is an electromagnet made from coils of superconducting wire. They must be cooled to cryogenic temperatures during operation. In its superconducting state the wire has no electrical resistance and therefore can conduct much larger electric currents than ordinary wire, creating intense magnetic fields. Superconducting magnets can produce stronger magnetic fields than all but the strongest non-superconducting electromagnets, and large superconducting magnets can be cheaper to operate because no energy is dissipated as heat in the windings. They are used in MRI instruments in hospitals, and in scientific equipment such as NMR spectrometers, mass spectrometers, fusion reactors and particle accelerators. They are also used for levitation, guidance and propulsion in a magnetic levitation (maglev) railway system being constructed in Japan.
Nuclear magnetic resonance spectroscopy, most commonly known as NMR spectroscopy or magnetic resonance spectroscopy (MRS), is a spectroscopic technique to observe local magnetic fields around atomic nuclei. This spectroscopy is based on the measurement of absorption of electromagnetic radiations in the radio frequency region from roughly 4 to 900 MHz. Absorption of radio waves in the presence of magnetic field is accompanied by a special type of nuclear transition, and for this reason, such type of spectroscopy is known as Nuclear Magnetic Resonance Spectroscopy. The sample is placed in a magnetic field and the NMR signal is produced by excitation of the nuclei sample with radio waves into nuclear magnetic resonance, which is detected with sensitive radio receivers. The intramolecular magnetic field around an atom in a molecule changes the resonance frequency, thus giving access to details of the electronic structure of a molecule and its individual functional groups. As the fields are unique or highly characteristic to individual compounds, in modern organic chemistry practice, NMR spectroscopy is the definitive method to identify monomolecular organic compounds.
In MRI and NMR spectroscopy, an observable nuclear spin polarization (magnetization) is created by a homogeneous magnetic field. This field makes the magnetic dipole moments of the sample precess at the resonance (Larmor) frequency of the nuclei. At thermal equilibrium, nuclear spins precess randomly about the direction of the applied field. They become abruptly phase coherent when they are hit by radiofrequency (RF) pulses at the resonant frequency, created orthogonal to the field. The RF pulses cause the population of spin-states to be perturbed from their thermal equilibrium value. The generated transverse magnetization can then induce a signal in an RF coil that can be detected and amplified by an RF receiver. The return of the longitudinal component of the magnetization to its equilibrium value is termed spin-latticerelaxation while the loss of phase-coherence of the spins is termed spin-spin relaxation, which is manifest as an observed free induction decay (FID).
Gregory Scott Boebinger was the director of the National High Magnetic Field Laboratory in Tallahassee, Florida, and is currently a professor of physics at Florida State University.
Naresh Dalal is a physical chemist who specializes in materials science. He is the Dirac Professor of Chemistry and Biochemistry at Florida State University, where he is affiliated with the National High Magnetic Field Laboratory. Dalal was first to synthesize Fe8.
Nuclear magnetic resonance (NMR) in the geomagnetic field is conventionally referred to as Earth's field NMR (EFNMR). EFNMR is a special case of low field NMR.
This page lists examples of magnetic induction B in teslas and gauss produced by various sources, grouped by orders of magnitude.
Nuclear magnetic resonance (NMR) is a physical phenomenon in which nuclei in a strong constant magnetic field are perturbed by a weak oscillating magnetic field and respond by producing an electromagnetic signal with a frequency characteristic of the magnetic field at the nucleus. This process occurs near resonance, when the oscillation frequency matches the intrinsic frequency of the nuclei, which depends on the strength of the static magnetic field, the chemical environment, and the magnetic properties of the isotope involved; in practical applications with static magnetic fields up to ca. 20 tesla, the frequency is similar to VHF and UHF television broadcasts (60–1000 MHz). NMR results from specific magnetic properties of certain atomic nuclei. Nuclear magnetic resonance spectroscopy is widely used to determine the structure of organic molecules in solution and study molecular physics and crystals as well as non-crystalline materials. NMR is also routinely used in advanced medical imaging techniques, such as in magnetic resonance imaging (MRI).
A Split Magnet is a resistive electromagnet that is separated into two halves, with the small gap that divides the two sides allowing access to a strong magnetic field. The combination of an accessible gap and strong magnetic field allows for the research of how far-infrared particles scatter. In addition, the magnet can also rotate up to 90°, allowing for the magnet to become parallel to the floor. The magnet uses a combination of 28 MW, a current of 160,000 amps and 13380 liters of water per minute used. The strongest split helix magnet in the world is currently located in Florida State University at the National High Magnetic Field Laboratory, and can generate a field of 25 Tesla.
Robert Guy Griffin is a Professor of Chemistry and director of the Francis Bitter Magnet Laboratory at Massachusetts Institute of Technology (MIT). He is known for his work in nuclear magnetic resonance (NMR) and developing high-field dynamic nuclear polarisation (DNP) for the study of biological solids. He has contributed many different methods and approaches now widely used in solid-state NMR spectroscopy, in particular in context of magic-angle-spinning NMR. For example, this extends to methods for resolution enhancement via heteronuclear decoupling, as well as techniques for polarisation transfer between nuclei.
A Benchtop nuclear magnetic resonance spectrometer refers to a Fourier transform nuclear magnetic resonance (FT-NMR) spectrometer that is significantly more compact and portable than the conventional equivalents, such that it is portable and can reside on a laboratory benchtop. This convenience comes from using permanent magnets, which have a lower magnetic field and decreased sensitivity compared to the much larger and more expensive cryogen cooled superconducting NMR magnets. Instead of requiring dedicated infrastructure, rooms and extensive installations these benchtop instruments can be placed directly on the bench in a lab and moved as necessary. These spectrometers offer improved workflow, even for novice users, as they are simpler and easy to use. They differ from relaxometers in that they can be used to measure high resolution NMR spectra and are not limited to the determination of relaxation or diffusion parameters.
The Laboratoire National des Champs Magnétiques Intenses is a research institution of the CNRS. It is based at two sites: one in Grenoble, specialised in static fields, and one in Toulouse, specialised in pulsed fields. The LNCMI provides a base for research related to high-strength magnetic fields by both resident scientists and visiting researchers from around the world. It is one of the three founding members of the European Magnetic Field Laboratory (EMFL) officially created in 2014.
James S. Hyde was an American biophysicist. He held the James S. Hyde chair in Biophysics at the Medical College of Wisconsin (MCW) where he specialized in magnetic resonance instrumentation and methodology development in two distinct areas: electron paramagnetic resonance (EPR) spectroscopy and magnetic resonance imaging (MRI). He is senior author of the widely cited 1995 paper by B.B. Biswal et al. reporting the discovery of resting state functional connectivity (fcMRI) in the human brain. He also served as Director of the National Biomedical EPR Center, a Research Resource supported by the National Institutes of Health. He was author of more than 400 peer-reviewed papers and review articles and held 35 U.S. Patents. He was recognized by Festschrifts in both EPR and fcMRI.
Geoffrey Bodenhausen is a French chemist specializing in nuclear magnetic resonance, being highly cited in his field. He is a Corresponding member of the Royal Netherlands Academy of Arts and Sciences and a Fellow of the American Physical Society. He is professeur émérite at the Department of Chemistry at the École Normale Supérieure (ENS) in Paris and professeur honoraire at the Laboratory of Biomolecular Magnetic Resonance of the École Polytechnique Fédérale de Lausanne (EPFL). He is a member of the editorial board of the journal Progress in Nuclear Magnetic Resonance Spectroscopy. He is the chair of the editorial board of the journal Magnetic Resonance.
Benjamin Lax was a solid-state and plasma physicist.
Lucio Frydman is an Israeli chemist whose research focuses on magnetic resonance imaging (MRI), nuclear magnetic resonance (NMR) and solid-state NMR. He was awarded the 2000 Günther Laukien Prize, the 2013 Russell Varian Prize and the 2021 Ernst Prize. He is Professor and Head of the Department of Chemical and Biological Physics at the Weizmann Institute of Science in Israel and Chief Scientist in Chemistry and Biology at the US National High Magnetic Field Laboratory in Tallahassee, Florida. He is a fellow of the International Society of Magnetic Resonance and of the International Society of Magnetic Resonance in Medicine. He was the Editor-in-Chief of the Journal of Magnetic Resonance (2011-2021).
Malcolm Harris Levitt is a British physical chemist and nuclear magnetic resonance (NMR) spectroscopist. He is Professor in Physical Chemistry at the University of Southampton and was elected a Fellow of the Royal Society in 2007.
Vivien Zapf is a research scientist at the National High Magnetic Field Laboratory pulsed field facility at Los Alamos National Laboratory.
Scott Crooker is a research scientist at the National High Magnetic Field Laboratory pulsed field facility at Los Alamos National Laboratory. He received his Ph.D. in physics from the University of California, Santa Barbara and his B.A. in physics from Cornell University. He is a Fellow of the Optical Society of America, a fellow of Los Alamos National Laboratory, a fellow of the American Association for the Advancement of Science and a fellow of the American Physical Society. He received a Los Alamos National Laboratory Fellow's Prize in 2007 for his outstanding research in the development of novel magneto-optical spectroscopies and their application to problems in solid state and atomic physics systems. In 2007 he also received a Los Alamos National Laboratory Outstanding Innovation Technology Transfer Award for a patent on multifunctional nanocrystals.
