Effect of insert material on artificial delamination performance in composite laminates

Delamination, a major cause of composite failure, is often simulated in experiments using artificial film inserts. In many cases the material used to create these inserts in not carefully controlled. Here a series of tensile tests were performed on central cut ply specimens with different insert film materials in both glass fibre epoxy (E-glass/913) and carbon fibre epoxy (IM7/8552) from which the mode II energy release rate can be calculated from the load at failure. When compared to specimens without inserts, some of the film inserts give a mode II the energy release rate, with considerable variation with film material. Also it was found that a change in specimen material can influence the effectiveness of the insert used.</p

A NEW SPECIES OF MILK FROG OF THE GENUS TRACHYCEPHALUS TSCHUDI (ANURA, HYLIDAE) FROM THE AMAZONIAN RAINFOREST

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)We describe a new species of Trachycephalus from the Amazon Rain Forest, which is morphologically similar to T. resinifictrix (Goeldi). This new species is characterized by a medium body size for species in the genus (males snout-vent length [SVL] 57.9-74.3 mm, females SVL 74.4-84.9 mm); skin of the head not co-ossified with underlying dermal bones; dorsal skin texture, including that of the head, densely glandulous with several tubercles; paired vocal sac that protrudes at a posterior angle to the jaw when inflated; iris coloration pinkish-beige with a horizontal black bar and a vertical thin black line below the pupil; dorsal color pattern consisting of a wide interocular whitish-beige and a dark blotch on the middle of the dorsum joining the crossbar at the top of the dorsum, forming a 'T' shape; rounded snout in dorsal view, and rounded or acuminate in profile; well-developed supratympanic fold; ulnar tubercles present, sometimes associated with ulnar fold; well-developed axillary membrane; well-developed tarsal fold; males with nonhypertrophied forearm; minimum frequencies of the advertisement call lower than 0.38 kHz; pulse rate 126.7-146.6 pulses/s; tadpole external coloration with brown reticulated blotches in the superior portion of the fin; tooth row formulae 2(2)/4. The new species, which is widely distributed in the Amazonian Forest, has been confused with the parapatric T. resinifictrix. It is a canopy treefrog that breeds in tree-holes that have accumulated rainwater.694466479Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ)Smithsonian Institution (Washington DC, USA)Universidade Federal do Para (UFPA)MPEGFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP