Zhao-Yun Wang,Lei Jin,Guang Li,Jia-Qiang Yang,Wei-Qing Li,DongPing Zhan,Yan-Xia Jiang,Fang-Zu Yang,Shi-Gang Sun
An organic additive, gentian violet (GVT), is explored for the first time as a novel leveler with excellent property in through-holes (THs) metallization of Cu electronic plating in acidic medium for printed circuit board (PCB) applications. Studies of galvanostatic measurements with a platinum rotation disk electrode and density functional theory calculations demonstrate that the GVT behaves the fundamental leveler's characteristics of mass transfer adsorption, and displays a strong inhibition effect on electro-reduction of cupric ions at high rotating rate. Although the adsorption ability of GVT on Cu surface is weaker than that of commercial leveler Janus Green B (JGB), the potential difference of cupric ion reduction between low and high rotating rates is larger in case of GVT than that of JGB at same current density. Cyclic voltammetry measurements indicate that the Cu amounts of cathodic deposition and that of anodic stripping tend to the same at both low and high rotating rates when GVT, Cl − , polyethylene glycol (PEG) and bis-(sodium sulfopropyl)-disulfide (SPS) coexist in the solution, demonstrating excellent synergistic action of these additives and super leveling effect. In situ FTIR spectroscopic analysis combined with cyclic voltammetry measurements illustrate that the GVT adsorbs on Cu surface and thus affects the electro-reduction of cupric ions, which reveals the very complicated synergistic actions of these additives, i.e., the adsorption ability of GVT can be slightly enhanced by Cl − , while it has been greatly enhanced in the presence of PEG which nevertheless decreases slightly the inhibition effect of PEG on electro-reduction of cupric ions; the SPS plays an antagonistic effect with GVT due to their competitive adsorption. Based on the characterization of GVT as a novel leveler, we developed a GVT-based formula of THs metallization of Cu electronic plating, and demonstrated an excellent efficiency of a throwing power of 97.6% at 10 mA·cm −2 in a real PCB THs metallization of Cu electronic plating.
Ce doped germanium dioxide nanowires with cubic GeO2 and tetragonal CeGeO4 phases have been synthesized by the hydrothermal route using sodium dodecyl sulfate (SDS) as the surfactant. The nanowires have the length and diameter of about 20 μm and 50–200 nm, respectively. The SDS assisted growth process is proposed to explain the formation of the Ce doped germanium dioxide nanowires. Ce doped germanium dioxide nanowires is used as the photocatalyst for the photocatalytic degradation of gentian violet (GV) under solar light irradiation. The roles of the solar light irradiation time, content of the nanowires and GV concentration on the photocatalytic degradation of GV are investigated. GV can be totally degraded under solar light irradiation for 240 min using 15 mg nanowires in 10 mL GV solution with the concentration of 10 mg · L−1. The Ce doped germanium dioixde nanowires show good application potential for the removal of organic pollutants under solar light irradiation. [DOI: 10.1380/ejssnt.2016.4]
Si-Fan Liu,Bin Lin,Yu-Fei Xi,Le Zhou,Li-Li Lou,Xiao-Xiao Huang,Xiao-Bo Wang,Shao-Jiang Song
Four pairs of new spiropyrrolizidine oxindole enantiomers (1a/1b–4a/4b) were isolated from the leaves of Isatis indigotica Fortune. Their structures and absolute configurations were elucidated by a combination of NMR spectroscopic analyses, experimental and calculated electronic circular dichroism (ECD) and the assistance of quantum chemical predictions (QCP) of 13C NMR chemical shifts. Notably, all the isolated spiropyrrolizidine oxindoles are reported as natural products for the first time. The biosynthetic pathway of these unique structures was proposed to be formed by cycloaddition reaction. In addition, all the compounds were evaluated for their inhibitory effects on β-amyloid aggregation by ThT assay, and the optically pure compounds 1a/1b and 2a/2b exhibited better Aβ1–42 aggregation inhibition potency (85.8% and 73.6%, 71.5% and 75.8%, respectively) at a concentration of 20 μM, compared with the positive control curcumin (57.0%). The difference of the inhibitory pattern caused by chirality was also explained by molecular docking studies.
危险品化学品经营许可证（带存储）