A study on the local corrosion behavior and mechanism of electroless Ni-P coatings under flow by using a wire beam electrode.

The local corrosion behavior and mechanism of Ni-P coatings in a 3.5 wt% sodium chloride solution with different flow speeds (0 m s-1, 0.5 m s-1, 1 m s-1) were investigated through a wire beam electrode (WBE) with morphological, elemental and electrochemical analyses as well as numerical simulations. It was found that the microstructure of the Ni-P coating was in the shape of broccoli and possessed satisfactory compactness and uniformity. The numerical simulations showed that the speed increased and the static pressure decreased at the local area. Combined with WBE, it was found that the average corrosion potential decreased at that area. The results indicated that the corrosion tendency and corrosion rate of the Ni-P coating were larger at higher speeds, and the corrosion resistance could be improved by the electroless Ni-P coating. WBE was helpful in revealing the local electrochemical information of the Ni-P coating.

One-pot formation of chiral polysubstituted 3,4-dihydropyrans via a novel organocatalytic domino sequence involving alkynal self-condensation.

The self-condensation of alkynals was for the first time implemented under mild organocatalytic conditions and was successfully linked with a domino organocatalytic inverse-electron-demand oxa-Diels-Alder reaction, which led to the development of a facile one-pot method to produce a wide variety of polysubstituted chiral 3,4-dihydropyrans with good to high yields and diastereoselectivities and high enantioselectivities. The unprecedented alkynal self-condensation was revealed to pass through secondary amine-catalyzed C-C triple bond hydration and subsequent aldol condensation.

[Expression of protein kinase C alpha in Chinese hamster ovary cells].

OBJECTIVE: To study the expression of protein kinase C (PKC) alpha subtype in Chinese hamster ovary (CHO) cells. METHODS: The PKC alpha primer pairs were designed based on the GenBank sequence of PKC alpha of a species with the highest homology to Chinese hamster identified using EMBL Data Library Clustalw tool. The sequence coding for PKC alpha, amplified from the CHO cells using RT-PCR, was ligated to the pGEM-T plasmid vector, and the recombinant vector was transformed into E.coli DH5alpha with the positive colones selected by blue/white screening. Restriction enzyme digestion, gel electrophoresis analysis, followed by sequencing of the digestion products were performed for identification of the recombinant. Western blotting was used to analyze the PKC alpha expression in the CHO cells. RESULTS: The presence of PKC alpha mRNA was detected in the CHO cells by RT-PCR. Western blotting also identified PKC alpha expression in the cells. CONCLUSIONS: PKC alpha expression has been identified in the CHO cells, which may facilitate further structural and functional study of PKC alpha and investigation of its role in the intracellular signal transduction pathways.