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In this study the autor provides a survey on the interaction between English and the Latin, French, Italian, Spanish and Potuguese is analyses chronologically, with a special regard to the phonological modifications of loan-words.
Abstract
Blends of poly(ether ketone) (PEK) with poly(terephthaloyl-imide) (a thermoplasticpolyimide, TPI) were studied by temperature-modulated DSC (TMDSC) and X-ray diffraction. Samples were prepared by compression moulding of the premixed materials at 400°C and quenched to prevent crystallisation.The amorphous blends showed a single glass transition but with a jump in the temperature value at 60 mass% of PEK, indicating limited miscibility of the system at both sides of the composition series in the quenched, glassy state. Two cold crystallisation peaks over the concentration range 30 to 70 mass% of PEK were observed, but only one for all other compositions. A single melting peak was observed in all systems.Blends crystallised from the glassy state showed eutectic behaviour with the presence of the crystals of both pure components. This is the first reported case of two semicrystalline polymers exhibiting eutectic co-crystallisation. The formation of eutectic crystals is proof of full miscibility of the two polymers in their liquid state, i.e. at a temperature of 400°C and above. Blends cooled from the melt at a cooling rate of 2 K min–1 showed a single glass transition and an extended melting range.Crystallisation during a second melting run generally starts at a different temperature then during the first run indicating chemical changes occurred in the molten state. This change was also verified by an exothermic peak above the melting temperature using TMDSC.
Abstract
Results for Se in several biological standard reference materials obtained by INAA and selective RNAA procedures developed in our laboratory, are presented and discussed. The comparison of selenium levels in selected blood plasma samples determined by non-destructive NAA and HG-AAS is also presented. The reproducibility and accuracy of the analytical procedure was tested and the results of these investigations were compared with the certified values.
Total daily Se intake was determined by duplicate diet collection, venous blood samples were taken and urine was collected over 24 h in order to measure selenium input and output in healthy, American and Hungarian children aged 8 to 17 living in Budapest. The American children consumed not only locally processed food. Food samples were weighed, mixed, homogenised and the Se content was determined by Instrumental neutron activation analysis (INAA). The Se concentration of blood, plasma and urine samples was determined by atomic absorption spectrometry-hydride generation (AAS-HG) after wet digestion. Se intake calculated for wet weight was 62±18.5 mg/day in American children. In the Hungarian children the mean Se intake was about 35% less than in the Americans. Se concentrations in plasma were 0.84±0.16, in whole blood 1.13±0.17 mmol l-1 in the Americans, higher than those in healthy Hungarian children (0.64±0.10 and 0.83±0.12 mmol l-1, respectively) of similar age and gender. Urinary Se output calculated for creatinin was higher in the children from abroad (27.0±9.5 mg Se/day/g creatinin) compared to Hungarians (11.0±5.0 mg Se/day/g creatinin).
