A new salicylaldehyde-based azo dye 5-azotriazolyl-3-methoxysalicylaldehyde (H2TMSA) and its two Ln3+ complexes {[Ln(HTMSA)3(H2O)2][Ln(HTMSA)3(DMF)(H2O)]}·15H2O (Ln = Dy(1) and Tb(2)) have been synthesized and characterized by IR, Raman, 1H NMR and single-crystal X-ray diffraction techniques. H2TMSA shows an azo form in acidic (pH < 5.05) and strong basic (pH > 12.41) conditions, and a pH-dependent azo-hydrazone tautomerism in the range of pH 5.05 to 12.41, which is demonstrated by the time-dependent density functional theory (TD-DFT) calculations. Single-crystal X-ray diffraction reveals that 1 and 2 are isostructural complexes in which the Ln3+ ions are surrounded by six oxygen atoms from three dichelate HTMSA- ligands and two oxygen atoms from two solvent molecules forming a distorted square-antiprismatic geometry. Complex 1 shows distinct slow magnetic relaxation under a zero dc field, while 2 displays field-induced slow magnetic relaxation. Ab initio calculations were performed on the two complexes to understand their magnetic anisotropy and their different magnetic dynamics.
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http://dx.doi.org/10.1039/c8dt02951b | DOI Listing |
J Magn Reson Imaging
January 2025
Department of Neurology, University of Texas Southwestern Medical Center, Dallas, Texas, USA.
Background: Central arterial stiffening is associated with brain white matter (WM) damage and gray matter (GM) volume loss in older adults, but little is known about this association from an adult lifespan perspective.
Purpose: To investigate the associations of central arterial stiffness with WM microstructural organization, WM lesion load, cortical thickness, and GM volume in healthy adults across the lifespan.
Study Type: This is a cross-sectional study.
Nanomaterials (Basel)
December 2024
Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, School of Materials Science and Engineering, Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China.
Cryogenic magnetic refrigerants based on the magnetocaloric effect (MCE) hold significant potential as substitutes for the expensive and scarce He-3. Gd(III)-based complexes are considered excellent candidates for low-temperature magnetic refrigerants. We have synthesized a series of Ln(III)-based metal-organic framework (MOF) (Ln = Gd/Dy) by the slow release of oxalates in situ from organic ligands (disodium edetate dehydrate (EDTA-2Na) and thiodiglycolic acid).
View Article and Find Full Text PDFJ Korean Neurosurg Soc
January 2025
Department of Neurosurgery, Kyung Hee University Hospital, Kyung Hee University College of Medicine, Seoul, Korea.
Objective: The leptomeningeal ivy sign is a distinctive finding of moyamoya disease (MMD), characterized by a linear high signal intensity along the cortical sulci on contrast-enhanced T1 magnetic resonance imaging (MRI) and fluid-attenuated inversion-recovery MRI. We recently identified a similar linear enhancement along the cortical sulci using gadolinium-enhanced vessel wall MRI (VWMR) in patients with MMD. The aim of this study was to introduce the concept of the "VWMR ivy sign (VIS)".
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
The College of Forestry, Beijing Forestry University, 100083, Beijing, PR China. Electronic address:
This study aims to address the challenge of detoxifying ginkgolic acid and transform it from waste into a valuable resource. By using pseudo-template molecular imprinting technology to chemically modify polysaccharide materials, we developed a polysaccharide-based molecular imprinted material (MMCC-CD/CS-MIP) for the targeted separation and controlled release of ginkgolic acid. Under optimal conditions, MMCC-CD/CS-MIP demonstrated excellent adsorption performance (Q = 47.
View Article and Find Full Text PDFNatl Sci Rev
January 2025
State Key Laboratory of Physical Chemistry of Solid Surfaces, School of Electronic Science and Engineering, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
Heterogeneous catalysts for parahydrogen-induced polarization (HET-PHIP) would be useful for producing highly sensitive contrasting agents for magnetic resonance imaging (MRI) in the liquid phase, as they can be removed by simple filtration. Although homogeneous hydrogenation catalysts are highly efficient for PHIP, their sensitivity decreases when anchored on porous supports due to slow substrate diffusion to the active sites and rapid depolarization within the channels. To address this challenge, we explored 2D metal-organic layers (MOLs) as supports for active Rh complexes with diverse phosphine ligands and tunable hydrogenation activities, taking advantage of the accessible active sites and chemical adaptability of the MOLs.
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