A molecular-mechanical link in shear-induced self-assembly of a functionalized biopolymeric fluid.
A molecular-mechanical link in shear-induced self-assembly of a functionalized biopolymeric fluid.
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DOI：
10.1039/d2sm01381a
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发表时间：
2023-05-03
期刊：
影响因子：
3.4
通讯作者：
Meersmann, Thomas
中科院分区：
文献类型：
--
作者：
Pavlovskaya, Galina E.;Meersmann, Thomas
采用23 Na多量子滤波（MQF）流变核磁共振（Rheo-NMR）方法研究了流动诱导角叉菜胶自组装的分子基础。该方法灵敏度足以利用约0.02%的内源性钠离子浓度。在不同温度和剪切速率下进行流变-NMR实验，以探索剪切下流体中生物聚合物的不同分子动力学。流变-NMR实验中的温度从288 K变化到313 K以捕获κ-卡拉胶分子从螺旋到卷曲的转变。在每个温度下，还使用体积流变学方法测试流体的流动和振荡剪切行为。发现对于0.5% κ-角叉菜胶溶液，仅在剪切下并且当流体表现出屈服和/或剪切稀化行为时观察到23 Na MQF信号。在303 K及以上的温度下，没有观察到23 Na MQF信号的存在或不存在的剪切作为分子相变到无规线圈发生和流体成为牛顿。 采用23 Na多量子滤波（MQF）流变核磁共振（Rheo-NMR）方法研究了流动诱导角叉菜胶自组装的分子基础。
23Na multiple quantum filtered (MQF) rheo-NMR methods were applied to probe the molecular foundation for flow induced self-assembly in 0.5% κ-carrageenan fluid. This method is sensitive enough to utilize an endogenous sodium ion concentration of approximately 0.02%. Rheo-NMR experiments were conducted at different temperatures and shear rates to explore varying molecular dynamics of the biopolymer in the fluid under shear. The temperature in the rheo-NMR experiments was changes from 288 K to 313 K to capture transition of κ-carrageenan molecules from helices to coils. At each temperature, the fluid was also tested for flow and oscillatory shear behaviour using bulk rheometry methods. It was found that the 23Na MQF signals were observed for the 0.5% κ-carrageenan solution only under shear and when the fluid demonstrated yielding and/or shear-thinning behaviour. At temperatures of 303 K and above, no 23Na MQF signals were observed independent of the presence or absence of shear as the molecular phase transition to random coils occurs and the fluid becomes Newtonian. 23Na multiple quantum filtered (MQF) rheo-NMR methods were applied to probe the molecular foundation for flow induced self-assembly in 0.5% κ-carrageenan fluid.
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影响因子：
10.7
作者：
Nunez-Santiago, M. C.;Tecante, Alberto;Doublier, Jean Louis
通讯作者：
Doublier, Jean Louis
DOI：
10.1016/s0141-8130(97)00054-8
发表时间：
1997-08-01
影响因子：
8.2
作者：
Piculell, L;Borgstrom, J;Viebke, C
通讯作者：
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影响因子：
3.3
作者：
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通讯作者：
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影响因子：
10.7
作者：
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通讯作者：
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影响因子：
3.4
作者：
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