No abstract

A new approach on usage of S‐1‐dodecyl‐S′‐(α,α′‐dimethyl‐α″‐acetic acid)trithiocarbonate (DDAT)‐covalently functionalized graphene oxide (GO) as reversible addition fragmentation chain transfer (RAFT) agent for growing of poly(N‐vinylcarbazole) (PVK) directly from the surface of GO was described. The PVK polymer covalently grafted onto GO has Mn of 8.05 × 103, and a polydispersity of 1.43. The resulting material PVK‐GO shows a good solubility in organic solvents when compared to GO, and a significant energy bandgap of ∼2.49 eV. Bistable electrical switching and nonvolatile rewritable memory effect, with a turn‐on voltage of about −1.7 V and an ON/OFF state current ratio in excess of 103, are demonstrated in the Al/PVK‐GO/ITO structure. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011

No abstract

For patients with obstructive jaundice associated with HCCA, current evidence indicate no superiority of PTBD over EBD regarding clinical feasibility and success rate, but data suggest a better clinical safety of PTBD compared with EBD in short-term postoperation. In long-term evaluation, the differences in clinical outcomes are not statistically significant between PTBD and EBD.