Characterization of nanoparticle transport through quartz and dolomite gravels by magnetic resonance imaging
Characterization of nanoparticle transport through quartz and dolomite gravels by magnetic resonance imaging
复制标题
通过磁共振成像表征纳米粒子通过石英和白云石砾石的传输
DOI：
10.1007/s13762-015-0767-4
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发表时间：
2015
影响因子：
3.1
通讯作者：
Lakshmanan S
中科院分区：
文献类型：
--
作者：
Lakshmanan S
磁共振成像（MRI）在揭示工程和地质系统中的输运过程方面具有巨大的潜力。在这里，我们利用MRI成像纳米粒子（NP）通过饱和的粗粒度系统的运输。使用市售的顺磁性标记的NP;顺磁性标记使得NP对MRI可见。NP运输成像为NP迁移通过填充柱的石英和白云石砾石。校准T2加权图像强度的变化，以提供在规则的时间间隔（T2是1H核的自旋-自旋弛豫时间）的NP浓度的完全定量图。由于纳米颗粒和白云石表面之间的静电吸引力，纳米颗粒的运输显着推迟白云石相比，石英。用CXTFIT计算机包评估NP浓度分布，以估计沿柱长度沿着多个点处的纳米颗粒传输参数。这提供了标准穿透曲线分析无法提供的时间分辨参数。颗粒-表面相互作用能分布通过Derjaguin-Landau-Verwey-Overbeek（DLVO）理论描述。随着距离的增加，色散系数和快沉积速率常数（kfast）增大，而沉积速率常数（k）和碰撞效率（α）减小。这些长度依赖的变化有显着的规模扩大的影响，用于预测NP运输模型在自然和工程粗粒度的系统，如可持续的城市排水系统和河床。
Magnetic resonance imaging (MRI) has tremendous potential for revealing transport processes in engineered and geologic systems. Here, we utilize MRI to image nanoparticle (NP) transport through a saturated coarse-grained system. Commercially available paramagnetically tagged NPs are used; the paramagnetic tag making the NP visible to MRI. NP transport was imaged as NPs migrated through packed columns of quartz and dolomite gravel. Changes in T2-weighted image intensity were calibrated to provide fully quantitative maps of NP concentration at regular time intervals (T2being the spin–spin relaxation time of1H nuclei). Transport of nanoparticles was significantly retarded in dolomite compared to quartz due to electrostatic attraction between nanoparticle and dolomite surfaces. NP concentration profiles were evaluated with the CXTFIT computer package to estimate nanoparticle transport parameters at multiple points along the length of the column. This provided temporally resolved parameters that standard breakthrough curve analysis cannot provide. Particle–surface interaction energy profiles were described through Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. While dispersion coefficients and fast deposition rate constant (kfast) were found to increase with distance, deposition rate constant (k) and collision efficiency (α) were found to decrease with distance. These length-dependant variations have significant scaling-up implications for transport models used to predict NP transport in natural and engineered coarse-grained systems, such as sustainable urban drainage systems and river beds.
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使用磁共振成像对砂质含水层基质中重金属离子的吸附和再活化进行时空观察。
影响因子：
11.4
作者：
N. Nestle;A. Wunderlich;R. Niessner;T. Baumann
通讯作者：
T. Baumann
人造纳米粒子：对某些地下水供应安全的新威胁？
DOI：
--
发表时间：
2011
期刊：
影响因子：
--
作者：
J. Tellam
通讯作者：
J. Tellam
影响因子：
4.4
作者：
Phoenix, V. R.;Holmes, W. M.
通讯作者：
Holmes, W. M.
DOI：
--
发表时间：
2010
期刊：
影响因子：
--
作者：
Jie Yu;J. Berlin;W. Lu;Lunliang Zhang;A. Kan;Ping Zhang;Erin E. Walsh;S. Work;Wei Chen;J. Tour;M. Wong;M. Tomson
通讯作者：
M. Tomson
影响因子：
3.6
作者：
Werth, Charles J.;Zhang, Changyong;Brusseau, Mark L.;Oostrom, Mart;Baumann, Thomas
通讯作者：
Baumann, Thomas