ELECTROCHEMICAL BEHAVIOURS OF LANTHANIDE FLUORIDES IN THE ELECTROLYSIS SYSTEM WITH LiF-NaF-KF SALT
As a part of partitioning studies, the experiments of cyclic voltammetry and electrolytic reduction with the liquid bismuth cathode were conducted to investigate electrochemical behaviours of lanthanide elements in the electrorefining system employing LiF-NaF-KF eutectic salt as the electrolyte. The cyclic voltammograms for NdF3 and GdF3 were obtained at various potential scan rates, respectively. The cathodic and anodic peak currents of the elements increased in proportion to the square root of the potential scan rate. According to changes of the potential difference between the coupled cathodic and anodic peaks, reversibilities of the reduction-oxidation reactions in this system were evaluated. In addition, further behaviours of electrochemical reaction of the elements were examined through electrolytic tests of the system using liquid bismuth as the cathode at fixed current densities.
Molten Salt Techniques
This fourth volume in the series opens some new arenas in the realm of molten salts technology, with research reports on amides, amide mixtures, and their electrochemical properties; chromatography in liquid organic salts; thermal conductivity; magnetic, calorimetric, and ultra-high-pressure measure
Failure analysis for poor solderability of Au surface of PCB
Nonwetting is one of the common problems and is always rejected in electronic assemblies. ENIG pads of a PCBA exhibited nonwetting after lead-free reflow soldering. With the aid of stereomicroscope, SEM&EDS and XRF, a series of analysis was performed. And after visual inspection, surface and cross section analysis, thickness measurement and solderability test, it can be inferred that oxidation of plating surface was the main reason for nonwetting, and corrosion in Ni plating caused an adverse impact on solderalibity.