Fagan Lyng (spleenblouse04)

DA oxidation and PDA formation were followed over time through the SERS band profile at pH 7, 9 and 12. We found that in situ PDA formation started after 50 min of laser irradiation of DA at pH 7, while DA was quickly oxidized at pH 9 and 12. Here, we present a detailed SERS band analysis of PDA, which sheds light on the molecular steps in the pathway formation of the PDA structure. Spectroscopic analysis and characterization revealed that a long laser exposure time led to the formation of stable PDA complexes with AgNPs, which allowed us to propose a novel approach for synthesis of AgNP-PDA composites. In conclusion, to detect DA through a label-free SERS approach, c-AgNPs must be employed, while stable AgNP-PDA materials can be achieved with h-AgNPs and 488 nm laser excitation.The potential use of a statistical approach for the investigation of complex dissolved organic matter (DOM) sources in surface water within a recycled water system monitored by excitation-emission matrix (EEM) fluorescence spectroscopy is shown. The work in this manuscript utilize information extracted from EEM spectroscopy to characterize DOM in collected surface water samples along with a wastewater treatment plant to drinking water treatment plant, discussing that humic-like and protein-like DOM sources predominate in the investigated water samples. Five different fluorescent components were resolved, describing several different types of DOM with different excitation and emission spectra that were distinct among the watershed sampling sites and indicating the influences of anthropogenic impacts. In addition, these novel fluorescence parameters have potential to improve resolution to direct more targeted water quality monitoring approaches.A fundamental understanding of cyclodextrin-closo-dodecaborate inclusion complexes is of great interest in supramolecular chemistry. Herein, we report a systematic investigation on the electronic structures and intramolecular interactions of perhalogenated closo-dodecaborate dianions B12X122- (X = F, Cl, Br and I) binding to α-, β-, and γ-cyclodextrins (CDs) in the gas phase using combined negative ion photoelectron spectroscopy (NIPES) and density functional theory (DFT) calculations. The vertical detachment energy (VDE) of each complex and electronic stabilization of each dianion due to the CD binding (ΔVDE, relative to the corresponding isolated B12X122-) are determined from the experiments along α-, β- and γ-CD in the form of VDE (ΔVDE) 4.00 (2.10), 4.33 (2.43), and 4.30 (2.40) eV in X = F; 4.09 (1.14), 4.64 (1.69), and 4.69 (1.74) eV in X = Cl; 4.11 (0.91), 4.58 (1.38), and 4.70 (1.50) eV in X = Br; and 3.54 (0.74), 3.88 (1.08), and 4.05 (1.25) eV in X = I, respectively. All complexes have significantly hment from CDs. Energy decomposition analyses reveal that the electrostatic interaction plays a dominating role in contributing to the host-guest interactions for the X = F series partially due to the formation of a O/C-HX-B hydrogen bonding network, and the dispersion forces gradually become important with the increase of halogen size.Polyoxovanadates (POVs), as one of the most prominent members of polyoxometalates (POMs), have been subject to extensive studies by virtue of their aesthetically intriguing structures and potential applications in catalysis, magnetism, and optics, among others. In recent years, organo-functionalized POVs have received considerable attention due to the combination of the advantages of POVs with the importance of organic species. In this review, the key developments of polyoxovanadates and, particularly, the achievements that are related to polyoxovanadates modified with organic ligands and transition metal-organic ligand are summarized. Herein, we systematically introduce the structural features of organo-functionalized POVs and their main applications involved in the magnetism and catalysis aspects. Finally, the current c