We present a detailed study on the acid-base behaviour of a family of "potentially antiaromatic" p-benzoquinonediimine ligands. These 12pi electron molecules can be considered as constituted of two chemically connected but electronically not conjugated 6pi-electron subunits. Upon successive protonation, "mono" and "double" cyanine-type chromophores are generated in solution and allow a precise and sensitive spectrophotometric detection. These molecules represent a new class of tunable quinones whose electronic and structural properties can be triggered by proton input, as established by a complete physico-chemical study involving a combination of potentiometric and spectrophotometric methods (absorption and emission).
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/chem.200305206 | DOI Listing |
Nanomaterials (Basel)
December 2024
Center On Nanoenergy Research, Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning 530004, China.
Wearable devices have potential applications in health monitoring and personalized healthcare due to their portability, conformability, and excellent mechanical flexibility. However, their performance is often limited by instability in acidic or basic environments. In this study, a flexible sensor with excellent stability based on a GaN nanoplate was developed through a simple and controllable fabrication process, where the linearity and stability remained at almost 99% of the original performance for 40 days in an air atmosphere.
View Article and Find Full Text PDFSensors (Basel)
November 2024
Department of Materials Science and Engineering, Inha University, Incheon 22212, Republic of Korea.
Semiconducting metal oxides with nanofiber (NF) morphologies are among the most promising materials for the realization of gas sensors. In this study, we have prepared electrospun ZnO-NiO composite NFs with different amounts of NiO (0, 20, 40, 60 and 80% wt%) for the systematic study of ethanol gas sensing. The fabricated composite NFs were annealed at 600 °C for crystallization.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
February 2025
College of Science, Chongqing University of Technology, Chongqing 400054, China.
In this paper, lanthanum and cerium co-doped carbon quantum dots (LaCe-CQDs) was firstly synthesized by one step hydrothermal method. The obtained LaCe-CQDs shown sable fluorescence properties with pH values from 3 to 9 and after 4 weeks of storage. The average particle size of LaCe-CQDs, with excitation and emission wavelengths of 350 nm and 446 nm, is 3.
View Article and Find Full Text PDFMolecules
October 2024
Faculty of Science and Engineering, Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands.
The linear diblock copolymer polystyrene--poly(4-vinylpyridine) (PS-P4VP) is an important copolymer recently used in many applications such as optoelectronics, sensors, catalysis, membranes, energy conversion, energy storage devices, photolithography, and biomedical applications. (1) Background: The surface thermodynamic properties of PS-P4VP copolymers are of great importance in many chemical and industrial processes. (2) Methods: The inverse gas chromatography (IGC) at infinite dilution was used for the experimental determination of the retention volumes of organic solvents adsorbed on copolymer surfaces as a function of temperature.
View Article and Find Full Text PDFFront Physiol
October 2024
Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT, United States.
Metabolic acidosis (MAc)-an extracellular pH (pH) decrease caused by a [HCO ] decrease at constant [CO]-usually causes intracellular pH (pH) to fall. Here we determine the extent to which the pH decrease depends on the pH decrease vs the concomitant [HCO ] decrease. We use rapid-mixing to generate out-of-equilibrium CO/HCO solutions in which we stabilize [CO] and [HCO ] while decreasing pH (pure acidosis, pAc), or stabilize [CO] and pH while decreasing [HCO ] (pure metabolic/down, pMet↓).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!