During bond back the deflection morphology converges to a fourfold, fivefold, and sixfold ridging pattern for the square, pentagonal and hexagonal films, respectively, showing a close resemblance with experimental film systems of similar size and shape. Rectangular films of large length to width ratio go through a transition in buckling shapes from the initial Euler mode, through the varicose mode into the antisymmetric telephone-cord mode. For all the film shapes, the ratio of the film height to the effective film width scales with the square root Compound Library clinical trial of eigenstrain and is independent of thickness. The bond-back mechanism determines the final wrinkle morphology and is governed by the eigenstrain

value at the end of the buckling-up stage and the dimensionless parameter (Gamma/EW(eq))(W(eq)/t)(3), relating the interface energy to the strain energy in the film. Selleck Kinase Inhibitor Library (C) 2011 American Institute of Physics. [doi:10.1063/1.3544467]“
“Different accelerated tests in 12 fuel cells stack were performed in laboratory, namely on/off, back-up, and base-load regimes. In parallel, membrane electrode assemblies (MEA) were integrated in two “”on-site”" systems for GSM relay application. One of them was

dedicated to base-load power applications while the second fuel cells coupled with photovoltaic panels operated in semibase load mode. To investigate the influence of the power profiles on MEA degradation, over 80 CCB MEAs (5 layers) were studied at different scales using ex situ characterizations such as tensile tests, TGA-MS, DMTA, and SEM. A series of complementary microstructural ageing markers were thereby identified. The isolated

influence of dry-wet cycling on MEA properties was also established after passive hydro-thermal (HT) ageing performed continuously for 10 months in the laboratory. The changes of each CA4P molecular weight marker as a function of HT ageing time permitted to define a temporal benchmark. Based on these indicators, the main changes occurred in the MEA properties appear after a 5 months dry-humid cycling (up to about 1800 cycles). The trends observed were useful to compare and estimate the degree of degradation of each ageing tests. Thus, the accelerated tests performed in laboratory for at least 500 h in stack did not reveal systematic MEA modifications. On the contrary, the 1500 h “”on-site”" system operation results in some MEA degradations which origins are discussed. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 120: 3501-3510, 2011″
“This paper describes the development of a method to characterize the temperature profile of silicon wafers in high-temperature environments. Monocrystalline wafers are implanted on one surface with B and P ions, which diffuse into the wafer at different rates based on the temperature-dependent diffusivity of the ions during a 30 min soak in the high-temperature environment between 1000 and 1400 degrees C.