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Carbon nanotubes (CNTs) have become strongly promising nano-particles for developing novel smart polymer matrix nanocomposites to satisfy the ever increasing design requirements of the recent avenues of space industry and other special structural applications. The objective of this paper is to investigate the influence of doped and dispersed CNTs in polymer matrix on its intrinsic properties. Three different types of polymers; polyvinylchloride (PVC), polymethylemethacrylate (PMMA), and polystyrene (PS) were subjected to this experimental investigation. CNTs/polymer matrix composites with a content ratio of CNTs up to 5% by weight were synthesized in lab. The nanocomposites were then characterized by measuring their mechanical, electrical, and thermal properties. In addition, thermo gravimetric analysis (TGA), Fourier transform infra red spectroscopy (FTIR), and scanning electron microscopy (SEM) were applied, and the results are presented and discussed. It can be generally concluded that both PMMA and PS polymers disclosed much better matching ability and cross linking ability with the interweaving CNTs than the PVC. Both PMMA and PS polymers may thus be nominated for further extension of the investigation to cover a wider range of CNTs content ratios in an endeavour towards searching for maximum specific performance properties of such nanocomposites.

Using high performance liquid chromatography, we analyzed tears from 50 patients with Graves' ophthalmopathy and 20 controls. With this technique, tear constituents are separated according to size; a normal tear protein profile consists of five peaks. An increase in one or more peaks was observed in 14 patients (28%) and in none of the controls. No decreased values were observed. No relation was observed between abnormalities of tear composition and the clinical NO SPECS classification. There was a tendency for increased tear protein peaks in those patients with longstanding disease. Most patients with an increase in one or more tear protein levels had normal thyroid function after treatment for hyperthyroidism. Our findings suggested that the inflammatory process in the orbit occurring in Graves' ophthalmopathy also had an effect on the lacrimal gland, which was reflected in the composition of the tears.