93Nb chemical shifts of [NbX6](-) (X = Cl, F, CO), [NbXCl4](-) (X = O, S), Nb2(OMe)10, Cp*2Nb(κ2-BH4), (Cp*Nb)2(µ-B2H6)2, CpNb(CO)4, and Cp2NbH3 are computed at the GIAO (gauge-including atomic orbitals)-, BPW91- and B3LYP-, and CSGT (continuous set of gauge transformations)-CAM-B3LYP, -ωB97, and -ωB97X levels, using BP86-optimized or experimental (X-ray) geometries. Experimental chemical shifts are best reproduced at the GIAO-BPW91 level when δ(93Nb) values of inorganic complexes are referenced directly relative to [NbCl6](-) and those of organometallic species are first calculated relative to [Nb(CO)6](-). An inadvertent error in the reported δ(93Nb) values of cyclopentadiene borane complexes (H. Brunner et al., J. Organomet. Chem.1992, 436, 313) is corrected. Trends in the observed 93Nb NMR linewidths for anionic niobates [Nb(CO)5](3-), [Nb(CO)5H](2-), and [Nb(CO)5(NH3)](-) are rationalized in terms of computed electric field gradients at the metal.
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http://dx.doi.org/10.1002/mrc.2624 | DOI Listing |
Spectrochim Acta A Mol Biomol Spectrosc
January 2025
Department of Obstetrics, The Second Hospital of Shandong University, Jinan 250033 PR China. Electronic address:
A fluorescent probe (NBC), constructed by benzothiazole-coumarin and naphthalimide derivatives, was developed for the detection of SO derivatives using the FRET (Förster Resonance Energy Transfer) strategy. NBC presented large Stokes shift (180 nm), fast response (2 min), high sensitivity (LOD: 45 nM) and an excellent linear relationship in response to SO derivatives. Moreover, NBC has been successfully applied to detect SO derivatives in food samples and living cells.
View Article and Find Full Text PDFDrug Metab Pharmacokinet
December 2024
Division of Pharmacology, Center for Biological Safety and Research, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa, 210-9501, Japan; Sojo University, Graduate School of Engineering, Department of Life Science, 4-22-1 Ikeda, Nishi-ku, Kumamoto City, Kumamoto, 816-0082, Japan. Electronic address:
Microphysiological systems (MPS) are gaining global attention as potential game-changers in pharmaceutical development. Since 2013, MPS suppliers from university laboratories in the United States and Europe have competed to develop these devices. After the development phase, the focus shifted to the accumulation of applications using MPS for pharmaceutical companies and end users.
View Article and Find Full Text PDFACS Nano
January 2025
College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, P. R. China.
Electrocatalytic CO-to-CO conversion with a high CO Faradaic efficiency (FE) at low overpotentials and industrial-level current densities is highly desirable but a huge challenge over non-noble metal catalysts. Herein, graphitic N-rich porous carbons supporting atomically dispersed nickel (NiN-O sites with an axial oxygen) were synthesized (denoted as O-Ni-N-GC) and applied as the cathode catalyst in a CORR flow cell. O-Ni-N-GC showed excellent selectivity with a FE over 92% at low overpotentials ranging from 17 to 60 mV, and over 99% at 80 mV.
View Article and Find Full Text PDFEnviron Pollut
January 2025
School of Fisheries, Aquaculture, and Aquatic Sciences, Auburn University, Auburn, AL. Electronic address:
Harmful algal blooms (HABs) cause severe economic and environmental impacts, including hypoxic events and the production of toxins and off-flavor compounds. Chemical treatments, such as copper sulfate pentahydrate (CuSO·5HO), are often used to mitigate the damaging effects of algal blooms. However, treatment effects are usually short-lived leading to waterbodies requiring repeated CuSO·5HO applications to control persistent algal blooms, particularly in highly eutrophic systems, such as aquaculture ponds or small agricultural impoundments.
View Article and Find Full Text PDFBiochemistry
January 2025
Department of Chemistry, Washington University in St. Louis, One Brookings Drive, St. Louis, Missouri 63130, United States.
Branch-point syntheses in nonribosomal peptide assembly are rare but useful strategies to generate tripodal peptides with advantageous hexadentate iron-chelating capabilities, as seen in siderophores. However, the chemical logic underlying the peptide branching by nonribosomal peptide synthetase (NRPS) often remains complex and elusive. Here, we review the common strategies for the biosynthesis of branched nonribosomal peptides (NRPs) and present our biochemical investigation on the NRPS-catalyzed assembly of fimsbactin A, a branched mixed-ligand siderophore produced by the human pathogenic strain .
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