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Nucleus Spectrometer Amplifier Power Level Avance BLA2BB ≥ + 6dB BLAX300/50 ≥ + 6dB BLAX300 ≥ + 6dB BLAX500 ≥ + 9dB BLAXH20 = - 6dB BLAXH40 = - 6dB BLAXH100/50 ≥ - 3dB BLAXH40 ≥ - 3dB BLAXH150/50 ≥ 0dB BLAXH300/50 ≥ 6dB BLAX300 ≥ + 6dB BLAX500 ≥ + 9dB Avance DPX 13 C Avance DRX Avance DMX 1.2 NMR Spectrometer The NMR spectrometer consists of three major components: (1) The superconducting magnet with the probe, which contains the sample to be measured; (2) The console, which contains all the electronics used for transmission and reception of radio frequency (rf) pulses through the preamplifier to the probe; (3) The computer, from where the operator runs the experiments and processes the acquired NMR data. 1.3 Classical Description of NMR A more complete theoretical description of NMR is given in chapter 22. Among the various atomic nuclei, about a hundred isotopes possess an intrinsic angular momentum, called spin and written hI . They also possess a magnetic moment µ which is proportional to their angular momentum: µ = γhI where γ is the gyromagnetic ratio. The Larmor theorem states that the motion of a magnetic moment in a magnetic field B0 is a precession around that field, where the precession frequency is given by: ω0 = −γB0 10 Larmor frequency BRUKER Avance 1D/2D
