Recent advances in application of 27Al NMR spectroscopy to …
网页2016年5月1日 · In liquid state, 27 Al NMR provides insights into structural, chemical, and dynamic properties of aluminum compounds, thanks to spectral parameters of the 27 Al nucleus such as chemical shifts, spin–spin couplings, linewidths, and relaxation times.
高场NMR实验揭示分子筛催化剂中的Al物种分布规律- X-MOL资讯
网页2021年5月31日 · 固体核磁共振（solid state NMR）是研究分子筛活性位的非常强有力的方法。 2020年，美国强磁场国家实验室（National High Magnetic Field Laboratory）的陈魁智博士及其同事与美国俄克拉荷马州立大学（Oklahoma State University）的Jeffery L. White实验室合作，利用19.6、35.2 T等强磁场NMR发现了分子筛ZSM-5中新活性位半交联骨架四配位铝Al (IV)-2*（J. Am. Chem. Soc., 2020, 142, 7514）。 近期，该团队对此课题的进一步研究 …
(27Al) Aluminum NMR
网页Al) Aluminum NMR. Use our NMR service that provides 27Ala NMR and many other NMR techniques. 27 Aluminum (27 Al)is a high sensitivity nucleus that yields broad lines over a wide chemical shift range. 27 Al is a spin 5/2 nucleus and is therefore quadrupolar. As a result, the signal width increases with asymmetry of the environment with somewhat ...
Distribution of Aluminum Species in Zeolite Catalysts: 27 Al NMR …
网页2021年4月21日 · Quantitative direct-excitation and sensitivity-enhanced 27 Al NMR techniques applied over the wide range of magnetic field strengths used in this study show that prior to significant hydrothermal exposure, detectable amounts of nonframework Al species do not exist.
ACS Cent Sci | 大连化物所侯广进团队:超高场固体NMR揭示γ-Al₂O₃ …
网页2022年6月8日 · 超高场27Al NMR可显著提高27Al核的检测灵敏度和分辨率。 为了进一步观察γ-Al2O3 和Al2O3-NS中不同配位状态铝之间的Al-O-Al连接方式，作者通过超高场 (35.2 T) 27Al-27AlDQ双量子实验进行了对比研究，该技术可直接获取Al-O-Al之间的连接信息。 对比 Al2O3-NS (图2b, d)，尽管γ-Al2O3中五配位仅占总铝含量的3%左右 (图2a)，但在27Al-27Al DQ谱图 (图2c) 中却显示出强烈的自相关信号 (V, V)。 该结果表明，存在于γ-Al2O3表面 …
Nature of Five-Coordinated Al in γ-Al - ACS Publications
网页2022年5月23日 · However, suffering from low intensity and spectral broadening for 27 Al NMR, very few detailed studies on the intrinsic structures related to these Al(V) species have been reported. With the advance of ultra-high-field NMR technology, the detection sensitivity and spectral resolution of the quadrupolar nucleus can be …
Recent advances in application of 27 Al NMR spectroscopy to …
网页2016年5月1日 · The structural characterization of aluminum-containing compounds by 27 Al nuclear magnetic resonance (NMR) spectroscopy, either in the liquid-state or in the solid-state, has become popular because of the recent progresses that nowadays make the acquisition and interpretation of the corresponding NMR spectra much easier.
In-depth 27Al NMR investigation of Al(C6F5)3 and its complexes …
网页2023年9月1日 · Therefore, the current work was aimed, first of all, to revise published 27Al NMR data of Al(C6F5)3 as the most widely used Al-based ‘super-electrophilic’ Lewis acid, and second, to summarize the detailed procedure how to acquire and process 27Al NMR spectra in challenging cases to obtain clear data.
Solid-state NMR spectroscopy | Nature Reviews Methods Primers
网页2021年1月14日 · Solid-state nuclear magnetic resonance (NMR) spectroscopy is an atomic-level method to determine the chemical structure, 3D structure and dynamics of solids and...
Recent advances in application of (27)Al NMR spectroscopy to
网页Valuable information about the local environment of the aluminum nucleus can be obtained through (27)Al Nuclear Magnetic Resonance (NMR) parameters like the isotropic chemical shift, scalar and quadrupolar coupling constants, and relaxation rate.
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