Production of highly aligned microfiber bundles from polymethyl methacrylate via stable jet electrospinning for organic solid-state lasers

The fabrication of micron-sized poly(methyl methacrylate) (PMMA) polymer optical fibers doped with rhodamine B as an organic dye is demonstrated. Highly aligned and defect-free fibers are fabricated by using the stable jet electrospinning (SJES) method and systematically varying critical parameters such as solvent type and polymer concentration. At optimal conditions, for example, a polymer concentration of 35 wt% of PMMA in butanone, ribbon-shaped fibers with a smooth surface and diameter of about 20 μm could be spun using SJES mode and deposited on a rotating drum as target in a highly aligned manner. Photoluminescence spectra of the doped fibers excited longitudinally and transversely with a laser show an excitation peak with full-width-at-half-maximum of only 5.05 nm and a low lasing threshold at a pump energy of 0.55 μJ, indicating that SJES could become a new source of amplified optics components or organic solid-state fiber lasers.     

Zur Reduction der allgemeinen Gleichung fünften Grades auf die Jerrard’sche Form—eine Weiterführung des von Hermite eingeschlagenen Weges

Ohne Zusammenfassung     

Self-Association and Self-Assembly of Molecular Clips in Water

Molecular clips functionalized with two sodium or ammonium benzoate groups self-assemble in water by means of a hydrophobically driven dimerization reaction. Depending on the counter ions, this self-assembly stops at the stage of the dimer (sodium) or continues to generate largenanometer-sized aggregates (ammonium). The molecules in the latteraggregates are proposed to be `glued' together by multiplehydrogen bonds between the ammonium counter ions and the benzoategroups of the clips.     

Zur Gerbmaterialanalyse (Richtigstellung)

Ohne Zusammenfassung     

Acetylene chemistry. Part 23 . N-vinylation on acridinones

The vinylation of 9(10H)-acridinones 1a-1d with propiolic acid ethylester resulting in acridinonyl-N-acrylic esters is reported.