- 1. The beginnings
- C.J.Görter, F.Bloch, M.E.Packard,... and their instruments
- 2. What does one need to build an NMR instrument
- Magnet, probehead, RF transmitter, RF receiver, ...
- 3. Excitation/Detection methods (E/D)
- Simultaneous E/D: continuous wave (CW) methods based on:
- Susceptivity variations (Q-meters, marginal oscillators)
- Absorption/dispersion: bridges or crossed coils
- Separate E/D: pulsed methods
- Other methods:
- Pseudo-CW (SSP), stochastic, Hadamard, correlation NMR, ...
- 4. Principal NMR applications
- High chemical resolution
- Analysis of chemical structure
- Stereochemical studies
- Molecular dynamics studies
- Low chemical resolution in vitro
- Analysis of materials (polymers,porous media,tissues,...)
- Studies of molecular dynamics and aggregation states
- Low chemical resolution in vivo
- MR imaging
- MR angiography
- Flow imaging
- Functional MR imaging
- Hybrid applications
- TMR with surface coils
- Spectroscopic imaging
- Geophysical applications
- Geo-imaging and prospecting
- Earth-field NMR magnetometers
- Industrial applications
- Quality assessment
- Process control
- 5. Generation of magnetic field
- Permanent magnets
- Components: yoke, poles, pole expansions, ...
- Materials: alnico, ferrites, rare earths, ...
- Auxiliary devices: thermostat, modulation coils, ...
- More components: energization coils, power supply, cooling system, ...
- Materials: low-hysteresis ferromagnetic alloys, ...
- Auxiliary devices: modulation coils, ...
- Low-temperature superconductors
- Components: main coil, cryo-switches, cryo-shims, ...
- Materials, including perspectives of high-temperature superconductors
- Cryogenic subsystem: dewars, transfer lines, liquid gases
- Quantum effects: once-only energization
- Air coils
- Merits: no saturation limits, possibility to cover large volumes
- Demerits: large power consumption
- Systems capable of fast variations of the field value
- Mechanical shuffling of the sample between two magnets
- FFC (fast field-cycling) and its technical pecularities
- Other sources of usable fields
- Internal fields of ferromagnetic materials
- Earth field
- Zero field (NQR)
- Comparative merits of various technologies
- 6. Magnetic field conditioning
- flux stabilizers, Hall probes, NMR 'lock'
- Improving field homogeneity
- mechanical and electrical 'shims', sample rotation
- Generation of field gradients
- Relative merits and application areas of the various devices
- 7. Generation of radiofrequencies
- Basic characteristics of a radiofrequency field
- frequency, phase, amplitude
- Trasmission of radiofrequencies
- coaxial cables and their characteristics, matching
- Modulation of radiofrequencies
- CW, pulses, gating, profiled pulses
- Use of multiple RF channels
- Lock channel (f0), Observe channel (f1), Decoupler channel (f2), ...
- Power RF amplifiers and their characteristics
- 8. The 'probe' (head, probehead, front-end, ...)
- Rewiev of solutions according to various applications:
- what is common and what changes
- Principal RF characteristics of a probe
- type of coil, bandwidth, Q-factor, tuning range, ...
- Accessories of a probe
- Sample temperature control system (VT)
- Field gradient coils/ Homospoil coils
- External NMR lock sub-system
- Coil/s for multiple resonances (such as decoupling)
- Other (MAS, He evaporator, high pressure, cooled coils, ...)
- 9. Detection of radiofrequencies
- general characteristics and constraints imposed by NMR
- Diode detectors
- linearization, envelope detectors, power detectors
- Phase detector (lock-in)
- Use of interfrequencies: when and why
- Dual-channel, quadrature detection
- Digital detection
- 10. NMR instrument control
- Fast events-sequence generator (pulser)
- 'Slow' interfaces and system busses
- 11. Handling of low-frequency signals
- Filters (anti-aliasing, analog, digital)
- Obsolete acquisition methods (historic perspective):
- Visual acquisition from a long-persistance scope
- Fotographic acquisition from a normal scope
- Digital scopes with memory
- Sample-and-Hold and Box-Car-Integrator devices
- Electromechanic recorders
- Modern A/D conversion and digital acquisition
- requirements and characteristics
- Accumulation and averaging of digital data
- The concept and its merits
- Dangers: overflow, aliasing, anomalous noise effects
- Phase cycling, pipe-lined pre-traetment, ...
- Dedicated systems versus generic computers
- 12. Evaluation of NMR data
- Types of evaluation:
- Filtering, window convolutions, integration, ...
- Artifacts suppression (mention methods such as MEM, LP, ...)
- FFT (spectroscopy, imaging) and its revolutionary contribution to HR-NMR
- Image reconstruction from k-space data (imaging)
- Types of evaluation reqested by different Applications
- Required characteristics of the employed data systems
NMR and MRI:
K-space and MRI
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