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The corrosion behavior of expandable tubular materials was investigated in simulated downhole formation water environments using a series of electrochemical techniques. The corrosion morphologies in the real downhole environment after three months of application were also observed by stereology microscopy and scanning electron microscopy (SEM). The results show that, compared with the unexpanded sample, the area of ferrite increases dramatically after a 7.09% expansion. The expanded material shows a higher corrosion current in the polarization curve and a lower corrosion resistance in the electrochemical impedance spectroscopy (EIS) plot at every studied temperature. The determined critical pitting temperatures (CPT) before and after expansion are 87.5°C and 79.2°C, respectively. SEM observations demonstrate stress corrosion cracks, and CO corrosion and HS corrosion also occur in the downhole environment. Due to additional defects generated during the plastic deformation, the corrosion performance of the expanded tubing deteriorates. [ABSTRACT FROM AUTHOR]

When designing drug carriers, the drug-to-carrier ratio is an important consideration, because the use of high quantities of carriers can result in toxicity as a consequence of poor metabolism and elimination of the carriers. However, these issues would be of less concern if both the drug and carrier had therapeutic effects. (−)-Epigallocatechin-3-O-gallate (EGCG), a major ingredient of green tea, has been shown, for example, to possess anticancer effects, anti-HIV effects, neuroprotective effects and DNA-protective effects. Here, we show that sequential self-assembly of the EGCG derivative with anticancer proteins leads to the formation of stable micellar nanocomplexes, which have greater anticancer effects in vitro and in vivo than the free protein. The micellar nanocomplex is obtained by complexation of oligomerized EGCG with the anticancer protein Herceptin to form the core, followed by complexation of poly(ethylene glycol)-EGCG to form the shell. When injected into mice, the Herceptin-loaded micellar nanocomplex demonstrates better tumour selectivity and growth reduction, as well as longer blood half-life, than free Herceptin. [ABSTRACT FROM AUTHOR]

The influence of tensile orientation, test environments and internal hydrogen contents on the room temperature tensile properties of a directionally solidified Ni3Al alloy was investigated. The specimens parallel to the growth direction exhibited a good ductility and little susceptibility to test environment. The values of elongation in vacuum, air and H2 are 39.7%, 39.2% and 29.7%, respectively. Also, a transgranular fracture mode was observed in the specimens. However, the specimens perpendicular to the growth direction exhibited lower ductility, much more sensitivity to test environment and intergranular fracture mode. The elongation values in vacuum, air and H2 are 13.7%, 10.3% and 3.3%, respectively. The results indicate that the cohesive strength of grain boundaries in the alloy is low and they are more susceptible to test environment than are grain interiors. In addition, only a slight embrittlement of the internal hydrogen was found in the specimens parallel to the growth direction. [ABSTRACT FROM AUTHOR]