Saponification value, the average molecular weight of fatty acids, is a crucial parameter for detecting adulteration of edible oils. Conventionally, it is determined in a laboratory setup through a time-consuming, laborious titration process using chemical reagents. Herein, the application of Raman spectroscopy for quick SV estimation of oils is demonstrated.
View Article and Find Full Text PDFThe creation of micrometer-sized sheets of silver at the air-water interface by direct deposition of electrospray-generated silver ions (Ag) on an aqueous dispersion of reduced graphene oxide (RGO), in ambient conditions, is reported. In the process of electrospray deposition (ESD), an electrohydrodynamic flow is created in the aqueous dispersion, and the graphene sheets assemble, forming a thin film at the air-water interface. The deposited Ag coalesce to make single-crystalline Ag sheets on top of this assembled graphene layer.
View Article and Find Full Text PDFWe present a catalyst-free route for the reduction of carbon dioxide integrated with the formation of a carbon-carbon bond at the air/water interface of negatively charged aqueous microdroplets, at ambient temperature. The reactions proceed through carbanion generation at the α-carbon of a ketone followed by nucleophilic addition to CO. Online mass spectrometry reveals that the product is an α-ketoacid.
View Article and Find Full Text PDFIn the ever-expanding realm of organic fluorophores, structurally simple and synthetically straightforward molecules with unique photophysical properties have received special attention. Among these, 1,4-dihydropyridine () is an important scaffold that permits fine-tuning of their photophysical properties through substituents on the periphery. Herein, we describe a series of solid-emissive N-substituted 2,6-dimethyl-4-methylene-1,4-dihydropyridine derivatives appended with electron-withdrawing substituents (dicyanomethylene or 2-dicyanomethylene-3-cyano-2,5-dihydrofuran) at the C-4 position and alkyl or alkylaryl groups on the nitrogen.
View Article and Find Full Text PDFThe synthetic feasibility and excellent luminescence features of organic molecules attracted much attention and were eventually found useful in lighting applications. In this context, a solvent-free organic liquid having attractive thermally activated delayed fluorescence features in bulk along with high processability has prime importance. Herein, we report a series of naphthalene monoimide-based solvent-free organic liquids exhibiting cyan to red thermally activated delayed fluorescence with luminescence quantum yields up to 80% and lifetimes between 10 to 45 μs.
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