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In the original publication, the formula and the calculated grafting ratio were incorrect, and the correction was depicted as follows:In virtue of the present proof on the grafting of CO onto the CN, element analysis was used to determine the grafting ratio (x Grafting ) of CO, i.e., the weight percentage of NCO-terminated PI-CO in CO-g-CN. Table 3 summarizes the experimental weight fractions of C, H, O, N and S elements for the CN and CO-g-CN and the theoretical values of C, O and N elements for NCO-terminated PI-CO. A small amount of the S element was derived from the sulfonic groups, which formed in the process of H 2 SO 4 hydrolysis. According to the weight fractions of the C element, the grafting ratio was calculated as 17.7 wt% by the following equation:where W CN , W CO-g-CN and W NCO-PI-CO are the experimental weight percentage of the C element in CN and CO-g-CN and the theoretical weight percentage of the C element in NCO-terminated PI-CO, respectively. In the part of ''Conclusions'' The results of FTIR, solid state 13 C NMR, and XPS proved that the CO was successfully grafted onto the surface of CN, and the weight percentage of grafting chains in CO-grafted CN (CO-g-CN) was determined as 17.7 wt% by element analysis.The online version of the original article can be found under

Plastic packaging materials tend to absorb moisture from ambient environment and get swollen, this may raise hygro-stress in plastic electronic package and redistribute the internal stress. In this paper, we reviewed the dramatic deformation of a plastic package (Flip Chip Plastic Ball Grid Array-FCPBGA) due to moisture absorption first, then hygro-thermo-mechanical stress of the plastic package and its evolution during a period of three months were investigated with finite element method, user development was performed for this investigation. The finite element model was verified with hygro-thermal deformation of the FCPBGA measured with a 3-D moiré interferometry system. Following findings were obtained: A. Thermal stress field was changed a lot due to moisture absorption; B. Thermal stress of chip was released to some extent, but peal stress up to 62.2MPa occurred to the solder bump, thus the danger of Under Bump Metal (UBM) opening increased.

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The aim of this study was to clarify the effects of acrylamide on mechanical and tribological properties of short carbon fiber-reinforced bisphenol-A-type epoxy composites. The short carbon fiber/epoxy-based composites with or without acrylamide were prepared by solution blending and moderate temperature-curing techniques. Obviously, the short carbon fiber resulted in the enhancement of flexural strength and modulus of the short carbon fiber/epoxy-based composites in contrast to the epoxy-based composites. When the loading-level of short carbon fiber was 8 parts (corresponding to 100 parts of the epoxy matrix), the short carbon fiber 8/epoxy composites containing the same loading-level of acrylamide showed the highest flexural strength and modulus. At the same time, it was found that the addition of acrylamide further improved strength, modulus of the short carbon fiber/epoxy-based composites. Furthermore, the friction coefficient values of the acrylamide-modified short carbon fiber 8/epoxy composites were lower than that without the addition of acrylamide. The worn morphologies observed by scanning electron microscope revealed that the wear mechanism of the acrylamide-modified short carbon fiber 8/epoxy composites was fatigue wear.