Polyester fibres structure modification using some organic solutions
The treatment causes only minor decrease in fi bre, i.e. yarn strength, while breaking elongation increases signifi cantly, almost up to 150 % in comparison to the untreated sample. Organic solvents, i.e. plasticizer solutions in the organic solvents mixture infl uence fi bre properties in a very favorable way, i.e. they can enable better dyeing, better moisture absorption, easier treatment in further phases of textile products manufacture and generally better usability. X-ray structural analysis was used to examine the infl uence of the treatment of polyester fi bres in the form of fi lament yarn, fi neness 75/26 dtex, with solutions 0.3, 0.6 and 0.9 % hydroquinone and α-naphtole in the solvent mixture which contained chlorophorm and methanol (solubility parameter δ=11.7) on changing of crystalline degree and crystallite size. It was found that treated fi bres showed sharper refl exion on diffractograms than untreated ones, i.e. they showed higher crystalline degree but smaller crystallite size.
Sorption of organic solvents by packaging materials: polyethylene terephthalate and TOPAS®
The sorption of organic solvents (1-butanol and 1-octanol) by polyethylene terephthalate and TOPAS® (cyclic olefin copolymers or COC) was investigated at 3, 23 and 42 °C and was studied by coupling two techniques (in an off-line way): supercritical fluid extraction to GC/MS. Supercritical fluid extraction (SFE) is widely perceived as a technique for the extraction of low to moderately polar compounds. The results obtained enable us to determine the corresponding diffusion coefficients and to show the relation existing between the diffusion coefficient and the following factors: the temperature, the size of diffusing molecules and the crystallinity degree of packaging materials. Therefore, the diffusions of 1-butanol and 1-octanol are less important in PET than in TOPAS® (completely amorphous).
Testing digital circuits using a Mixed-Signal Automatic Test Equipment
This paper presents the results of parametric testing of digital ICs using a dedicated Mixed Signal Automatic Testing Equipment. Due to the prohibitive price of the ATE equipment and dedicated Device Interface Board (DIB) for digital Integrated Circuits (ICs), a DIB for analog circuits was used to perform the testing. Despite the challenges presented by the experiments, the results prove to be accurate for the performed tests, according to the data sheet of the digital ICs and production test data provided by the manufacturer.