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Updated: Jun 22, 2025

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
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一个数值模拟方法来分析H自旋扩散NMR用于多元组件和多相聚合物系统.

Xuran Jin1, Wei Chen2

  • 1National Synchrotron Radiation Laboratory, Anhui Provincial Engineering Laboratory of Advanced Functional Polymer Film, CAS Key Laboratory of Soft Matter Chemistry, University of Science and Technology of China, Hefei, 230026, China.

Solid state nuclear magnetic resonance
|June 29, 2024
PubMed
概括

一种新的仿真方法,SDNMR-WEBFIT,使用质子旋转扩散NMR精确量化聚合物相间动力学. 它测量了复杂的聚合物系统中的放松时间和扩散系数等关键性质.

关键词:
莱文伯格 - 马奎特算法 (L-M算法)数字模拟 数字模拟伪二维的扩散模型.旋转扩散是指旋转扩散.

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Interpreting ¹H NMR Signal Splitting: The (n + 1) Rule

In the AX proton spin system, proton A can sense the two spin states of a coupled proton X, resulting in a doublet NMR signal with two peaks of equal (1:1) intensity. When proton A is coupled to two equivalent protons (AX2 spin system), the spin states of each X can be aligned with or against the external field, creating three possible scenarios. This results in a 1:2:1  triplet signal, where the central peak corresponds to the chemical shift of A and is twice as large or intense as the...
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Spin systems where the difference in chemical shifts of the coupled nuclei is greater than ten times J are called first-order spin systems. These nuclei are weakly coupled, and their chemical shifts and coupling constant can generally be estimated from the well-separated signals in the spectrum.
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¹H NMR Signal Multiplicity: Splitting Patterns01:13

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