ISO_NWIPs-for-Ballot

ISO/NP

115

3.12 relaxation time 116 time constant, required for nucleus to obtain an equilibrium state in a magnetic field and to return to 117 that state after excitation with a radio frequency pulse. 118 3.13 119 chemical shift 120 δ 121 relative difference, in an NMR spectrum, between the resonant frequencies of a nucleus and that of a 122 reference material (conventionally: The 1 H resonance signals of Tetra Methyl Silan areset to zero ppm) 123 Note 1 to entry: Chemical shift is expressed in parts per million (ppm) 124 Note 2 to entry: The chemical shift reference frequency for 1 H NMR is that of TMS, set to δ = 0 ppm. 125 3.14 126 spin-spin coupling 127 J coupling 128 spin coupling 129 effect of covalently-bound nuclear spins on each other, causing splitting of their resonance signals 130 3.15 131 spin-spin coupling constant 132 J coupling constant 133 J value 134 spin coupling constant 135 magnitude of the effect of covalently-bound nuclear spins on each other, expressed in Hz 136 3.16 137 NMR spectrum 138 all NMR resonances acquired within a chemical shift region 139 3.17 140 signal area 141 area under the curve of a resonance 142 3.18 143 pulse flip angle 144 tilt angle of the nuclear magnetization vector, relative to the static magnetic field when applying an RF 145 pulse of specific duration and amplitude in a static magnetic field at thermal equilibrium 146 3.19 147 equilibriummagnetization 148 macroscopic magnetic state of an object when placed in a statice magentic field and left for some time to reach the 149 equilibrium state. 150 151 3.20 152 repetition 153 timeperiod of time from the application of the first pulse of a pulse sequence until the same pulse is 154 applied 155 3.21 156 1 H qNMR spectrum 157 frequency domain NMR spectrum obtained using quantitative NMR conditions with hydrogen ( 1 H) as 158 the observed nucleus 159

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