A global bifurcation scenario for a two-frequency torus breakdown depicted by Baptista and Caldas [Physica D 132, 325 (1999)] is observed on a glow-discharge experiment. The torus is broken through a crisis with an unstable periodic orbit. The torus section before the bifurcation is a sided polygon that has a number of edges equal to the period of the unstable orbit. Since the discharge is an extended system the two-frequency torus breakdown is shown to be a possible way to space-time chaos.

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The surface properties of commercially cost-effective cotton/polyester blended textiles (50%/50%) are modified using dc low-pressure air discharge. Surface modifications are analyzed at different plasma conditions. The macroscopic effects are investigated by measurements of the contact angles, Fourier's transform spectroscope (FTIR), x-Ray Diffraction (XRD), and the scanning electron microscope (SEM), which are examining the morphology of the treated surface and chemical shift. Atomic force microscopy (AFM) assesses the roughness of the treated textile surface. Furthermore, the mechanical characteristics of textiles are measured. The results indicate improved hydrophilicity of blend textiles and refinement of dyeability. In addition, the results of XRD, SEM images provided visual evidence that the dc air plasma treatment could be improved the wettability of blended textiles where the surface etching renders the blend textiles less crystalline and more hydrophilic and AFM results revealed that the plasma treatment was a good technique to increase the roughness of blend textile surface. In addition, the FTIR analysis indicated the presence of functional groups on the blend textile surface after plasma treatment. The results found that the improvements in surface properties are dependent on treatment time.

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