Unsymmetrical one-pot sequential cross-coupling reactions of sterically hindered tetrabromo thiophene with aryl boronic acid and alkyne/alkene to afford selective bi-, tri-, and tetrasubstituted aryl/alkynyl-thiophenes with the aid of a palladium catalyst were described. Reaction proceeds via a site-selectiv
The synthesis and characterization of a series of donor-π-acceptor-π-donor (D-A-D) curcuminoid molecules are here presented incorporating π-extended aryl and electron-donating amino terminal functionalization. Computational evaluation shows these molecules possess quadrupolar character with the lowest energy transitions displaying high molar extinction coefficients with broad tunability through manipulation of terminal donating groups. Consistent with their quadrupolar nature, these molecules show varying degrees of solvatochromic behavior in both their absorption and emission spectra which has been analyzed by Lippert-Mataga and Kamlet-Taft analysis. Photophysical and photoacoustic (PA) properties of these molecules have been investigated by the optical photoacoustic z-scan (OPAZ) method, which found select curcuminoid molecules display nonlinear behavior at a high laser fluence through excited state absorption that translates to the production of an enhanced photoacoustic emission. A relative comparison ...
Here, we report three different methods to determine the volume phase transition temperature (VPTT) of various systems including poly(N-isopropylacrylamide) (pNIPAm) based nanogels, Au nanoclusters and a combination of inorganic and polymeric systems. Although all the methods reveal close VPTT values, we suggest th
Magnetic microspheres (MM) were prepared using calcium alginate (CA) encapsulated biochar (BC) and Fe3O4 as a high-performance green absorbent for Cu(ii) removal from aqueous solution. The effects of the initial Cu(ii) concentration, initial pH value of the Cu(ii) solution and equilibrium contact time were investig
A convenient and green synthetic route using calcium ion induction was first used to prepare peanut protein isolate (PPI) nanoparticles. Through dynamic light scattering (DLS) and transmission electron microscopy (TEM), the role of each procedure in the formation of nanoparticles was systematically investigated by
Semiconductor–graphene composites have been widely reported as photocatalysts for hydrogen generation. The structure of the semiconductor, intimate interfacial contact between the components, and high electrical conductivity of the catalyst support can affect the performance of semiconductor–graphene composite phot
Graphene oxide/Fe3O4@polythionine (GO/Fe3O4@PTh) nanocomposite was fabricated as a new and promising sorbent for magnetic dispersive solid-phase extraction (MDSPE) and high-performance liquid chromatography-ultraviolent detection (HPLC) of chlorpheniramine in human plasma. To fabricate the sorbent, thionine was pol
Highly uniform core–shell polypyrrole@carbon microspheres (PPy@CM) have been successfully constructed by oxidation polymerization of pyrrole as the shell on the core of carbon microspheres. The thickness of the PPy shell can be easily controlled by modulating the weight ratio of pyrrole monomer and carbon microsphe