The Raman band at about 870 cm originating from the symmetric stretch vibration (ν) of uranyl, UO, has proven to be very informative for investigating the complexation of uranyl using perchlorate or nitrate of known concentration as internal standards. The concentration of uranyl can be conveniently calculated by using the ratio of the directly read band intensities of uranyl and the added reference, ClO, with a factor of 1.72. While with NO of concentration lower than 1.8 M as the reference, a factor of 0.85 should be used. Furthermore, with added internal standards, the linear relationship between the Raman intensity and the concentration of the corresponding species is illustrated by the spectral titration of U(vi) with a very strong ligand, dipicolinic acid (DPA); and the application of a spectral titration method with Raman spectroscopy in studying the complexation of uranyl is demonstrated by the titration of U(vi) with oxalate. The stepwise changes in the Raman shift of 18, 17, and 6 cm, corresponding to the three oxalate anions successively bonding to UO, imply that the coordination modes are different. In the 1 : 1 and 1 : 2 ratios of metal to ligand complexes, the oxalate anions bond to the uranyl ion in side-on bidentate mode, but in the 1 : 3 complex the third oxalate bonds in head-on mode, which is much weaker than the first two.
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http://dx.doi.org/10.1039/c7dt01631j | DOI Listing |
Inorg Chem
March 2025
Luminescent Materials Laboratory, DB, University of Verona, and INSTM, UdR Verona, Verona 37134, Italy.
In this contribution, we present new NIR-CPL/CD active Yb(III) complexes, which are synthesized by combining two ligands characterized by different types of chirality: central and axial chirality. The ligand bearing central chirality is represented by the neutral -,'-bis(2-pyridylmethylidene)-1,2-(, or ,) cyclohexanediamine (), whereas the axial ligand is 1,1'-binaphthyl-2,2'-diol (BINOL-H). A combined H NMR, thermodynamic (spectrophotometric titrations), and theoretical (DFT structural calculations) study is presented, revealing the high stability in the methanol solution of the homochiral -symmetric anionic [Yb(BINOL)] complexes, in which the two labile BINOLate molecules exhibit the same stereochemistry ( or ).
View Article and Find Full Text PDFAnimals (Basel)
March 2025
Department of Veterinary Administration, College of Veterinary Medicine, Purdue University, West Lafayette, IN 47907, USA.
This study evaluated electroencephalogram [EEG] and cardiovascular correlation of sevoflurane anesthesia in healthy beagle dogs at varying minimum alveolar concentration (MAC) multiples. Processed EEG indices (Patient State Index [PSI], burst suppression ratio [SR], and Spectral Edge Frequency [SEF95], cardiovascular parameters (mean blood pressure [MBP], heart rate [HR]), and responses to noxious (electrical) stimuli were recorded. Deep anesthesia (2.
View Article and Find Full Text PDFUnlabelled: Light-gated ion channels from protists (channelrhodopsins or ChRs) are optogenetic tools widely used for controlling neurons and cardiomyocytes. Multiplex optogenetic applications require spectrally separated molecules that must be found in nature, as they are difficult to engineer without disrupting channel function. Scanning numerous sequence databases, we identified three robust naturally blue-shifted ChRs from ancyromonads.
View Article and Find Full Text PDFLuminescence
March 2025
Department of Genetic Engineering, Madurai Kamaraj University, Madurai, India.
An efficient isoquinoline-fused benzimidazole-based "turn-on" fluorescence receptor 9,10-bis(2-phenylhydrazineyl)-7H-benzo[de]imidazo[2,1-a]isoquinolin-7-one OXPH(ANQ) and "turn-off" fluorescence receptor 9,10-bis((3-(1H-imidazol-1-yl)propyl)amino)-7H-benzo[de]imidazo[2,1-a]isoquinolin-7-one OXPID(ANQ) were prepared and characterized by various spectral techniques. The sensing behavior of receptors was demonstrated by UV-vis and fluorescence experiments, and naked-eye detection exhibited prominent visual emission color change toward Cu/Cl and Fe over other testing cations/anions in DMSO:water (9:1, ν/v) solution. The 1:1 binding stoichiometry was confirmed by Job's plot, FT-IR, mass spectral titration, and also DFT studies with target ions as evidence for the binding nature of OXPH(ANQ)/OXPID(ANQ) with Cu/Cl and Fe ions, respectively.
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
July 2024
In this work, we propose a semi-autonomous device to measure the absorbance spectrum of a sample with high spectral resolution and high intensity precision to address the previously mentioned issues. The proposed system includes integrated optical, microfluidic and electronic modules. The optical module is based on a polychromator spectrophotometer using a Grism diffractive component for a high spectral resolution.
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