Red Emission of Eu（lll） Complex Based on 1-（7-（ferf-butyl）-g-ethyl-gH- carbazol-2-yl）-4,4,4-trifluorobutane-l,3-dione Excited by Blue Light

A new Eu（III） complex, EuL3（phen）, was synthesized, where L is the abbreviation of de- protonated 1-（7-（tert-butyl）-9-ethyl-gH-carbazol-2-yl）-4,4,4-trifluorobutane-l,3-dione （HL）, phen is the abbreviation of 1,10-phenanthroline. The Eu（III） complex was characterized by element analysis, IR, 1H NMR, UV-visible absorption spectroscopy, thermogravimetric anal- ysis （TGA）, and photoluminescence measurements （PL）. TGA shows that thermal stability of the complex is up to 325 ~C. PL measurement indicates that the Eu（III） complex exhibits intense red-emission and extends their excitation bands to visible region. LEDs device was successfully fabricated by precoating complex EuL3 （phen） onto 460 nm blue-emitting InGaN chip. The emission of device shows that the complex can act as red phosphor in combination with 460 nm blue-emitting chips. This europium complex based on 1-（7-（tert-butyl）-9- ethyl-9H-carbazol-2-yl）-4,4,4-trifluorobutane-l,3-dione is a kind of interesting red-emitting material excited by blue light, which could avoid the damage of excitation by UV light.

Research on conductive-material-filled electrodes for sidewall insulation performance in micro electrochemical machining

In micro electrochemical machining(ECM)processes,stray corrosion causes undesired metal dissolution and the deterioration of shape accuracy.Adopting a sidewall-insulated electrode is an effective approach to suppressing stray corrosion.Most sidewall-insulated electrodes are made of metal substrate and non-metallic thin films.Nevertheless,the thin-film insulating materials attached to a metal substrate are susceptible to damage in an electrolytic environment.This study presents a novel concept of the conductive-material-filled electrode for better sidewallinsulation performance.The micro-scale quartz tube serves as the insulating substrate.Commercially available conductive fillers including metal wire,molten metals,and silver powder are filled inside the working cathode of the quartz tube.Consequently,the metal-wire-filled electrode,moltenmetal-filled electrode,and nano-powder-filled electrode are designed and fabricated.From the verification results of electrode toughness,material removal rate,and surface topography,the metal-wire-filled electrode and moltenmetal-filled electrode exhibit the same performance as a traditional metal-based electrode and much better durability.By contrast,the nano-powder-filled electrode is unable to withstand long-term ECM processes because of the loss of cured powder particles.In ECM experiments,microstructures with steep sidewalls(taper angle<9.7°)were machined using the metal-wire-filled electrode and molten-metal-filled electrode,which could replace the traditional electrode,achieving a longer service life and superior sidewall-insulation performance.