Energy level splitting in a magnetic field (H-nuclei)
FID signal
Spin echo signal
Acquired signal
Calculation of transversal relaxation time T2
Features
10 easy-to-use specimen tubes
High homogeneous magnetic field
Stable & reliable experiment data
Friendly software & convenient operation
Introduction
Pulsed nuclear magnetic resonance (PNMR) applies a pulsed RF field to the nuclei system and observes the response of the nuclei system. The fast Fourier transformation (FFT) technology is used to transform the time domain signal into a frequency domain signal, which is equivalent to multiple single-frequency continuous wave nuclear magnetic resonance (CW-NMR) spectrometers at the same time. Therefore, the nuclear magnetic resonance phenomenon can be observed in a larger range, and the signal amplitude is twice as large as the CW ones.
LEAI-13 PNMR Apparatus uses DDS digital synthesis technology for the transmitting pulse source and PID control technology for the temperature control of the magnet. The experimental data is stable and reliable, the operation is convenient, and the experiment contents are rich, which can be used in advanced physics labs in colleges and universities.
LEAI-13 PNMR Apparatus consists of a Constant Temperature Unit (including magnet and temperature control device), a RF Transmitting Unit (including power supply of modulation field), and a Signal Receiving Unit (including power supply of homogenous field and temperature display). A computer is also required for running the program of experiments.
Using this instrument, the following experimental objectives can be achieved:
1. Understand the basic physical theory and experimental configuration of a PNMR system. Learn to explain related physical phenomena in PNMR using classical vector model.
2. Learn to use signals of spin echo (SE) and free induction decay (FID) to measure T2 (spin-spin relaxation time). Analyze the influence of magnetic field homogeneity on NMR signal.
3. Learn to measure T1 (spin-lattice relaxation time) using reverse recovery.
4. Qualitatively understand the relaxation mechanism, observe the effect of paramagnetic ions on nuclear relaxation time.
5. Measure T2 of copper sulfate solution at different concentrations. Determine the relationship of T2 with the change of concentration.
6. Measure the relative chemical displacement of the specimen.
The instruction manual contains comprehensive materials including experimental configurations, principles and step-by-step instructions. Please click Experiment Theory and Contents to find more information about this apparatus.
Specifications
| Description | Specifications |
| Power supply of modulation field | maximum current 0.5 A, voltage regulation 0 - 6.00 V |
| Power supply of homogenous field | maximum current 0.5 A, voltage regulation 0 - 6.00 V |
| Oscillator frequency | 20 MHz |
| Magnetic field strength | 0.470 T |
| Magnetic pole diameter | 100 mm |
| Magnetic pole distance | 20 mm |
| Magnetic field homogeneity | 20 ppm (10 mm × 10 mm × 10 mm) |
| Controlled temperature | 36.500 °C |
| Magnetic field stability | 4 hours warm to be stabilized, Larmor frequency drift less than 5 Hz per minute. |
Parts List
| Description | Qty | Note |
| Constant Temperature Unit | 1 | including magnet and temperature control device |
| RF Transmitting Unit | 1 | including power supply of modulation field |
| Signal Receiving Unit | 1 | including power supply of homogenous field and temperature display |
| Power Cord | 1 | |
| Various Cable | 12 | |
| Specimen Tubes | 10 | |
| Instructional Manual | 1 |
Energy level splitting in a magnetic field (H-nuclei)
FID signal
Spin echo signal
Acquired signal
Calculation of transversal relaxation time T2
