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Abstract：
1H fast field-cycling and time-domain nuclear magnetic resonance relaxometry studies have been performed for 15 samples of sugar of different kinds and origins (brown, white, cane, beet sugar). The extensive data set, including results for crystal sugar and sugar/water mixtures, has been thoroughly analyzed, with a focus on identifying relaxation contributions associated with the solid and liquid fractions of the systems and non-exponentiality of the relaxation processes. It has been observed that 1H spin-lattice relaxation rates for crystal sugar (solid) vary between 0.45 s-1 and 0.59 s-1, and the relaxation process shows only small deviations from exponentiality (a quantitative measure of the exponentiality has been provided). The 1H spin-lattice relaxation process for sugar/water mixtures has turned out to be bi-exponential, with the relaxation rates varying between about 13 s-1-17 s-1 (for the faster component) and about 2.1 s-1-3.5 s-1 (for the slower component), with the ratio between the amplitudes of the relaxation contributions ranging between 2.8 and 4.2. The narrow ranges in which the parameters vary make them a promising marker of the quality and authenticity of sugar.
摘要：
已对15种不同种类和来源的糖样品进行了1H快速场循环和时域核磁共振弛豫测定研究（棕色，白色,甘蔗,甜菜糖）。广泛的数据集，包括结晶糖和糖/水混合物的结果，已经被彻底分析了，重点是确定与系统的固体和液体部分以及松弛过程的非指数性相关的松弛贡献。已经观察到，晶体糖（固体）的1H自旋晶格弛豫速率在0.45s-1和0.59s-1之间变化，并且弛豫过程仅显示出与指数性的小偏差（已提供了指数性的定量度量）。糖/水混合物的1H自旋晶格弛豫过程已被证明是双指数的，弛豫率在约13s-1-17s-1（对于较快的组件）和约2.1s-1-3.5s-1（对于较慢的组件）之间变化，松弛贡献的振幅之间的比率在2.8和4.2之间。参数变化的狭窄范围使其成为糖的质量和真实性的有希望的标记。
