#NMR

In NMR (Nuclear Magnetic Resonance) spectroscopy, the term "hold" or "close" typically refers to the settings related to the stability and locking of the magnetic field or the sample in the instrument. "Hold" refers to the practice of maintaining a consistent experimental condition, ensuring that the magnetic field and frequency remain stable during the analysis. On the other hand, "close" usually refers to fine-tuning or adjusting the instrument to ensure that the resonance frequencies of nuclei are correctly aligned for accurate results. Properly managing these aspects is crucial for high-quality, reliable NMR spectra.