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Thin, flexible and tough bucky paper fabricated by filtering a stable suspension of double walled carbon nanotubes (DWNTs) was characterized from the viewpoint of its pore structure and oxidation stability as compared with that derived from single-walled carbon nanotubes (SWNTs). The N 2 adsorption isotherms of DWNTs and SWNTs at 77K were of type II and type IV, respectively, and also the micropore volume in DWNTs was three times greater than that in SWNTs. The onset temperature of oxidation in DWNTs was enhanced by ca. 200 o C due to their coaxial structure. The expected high mechanical and electrical properties when combined with their high surface area and high structural integrity make the DWNTs bucky paper promising materials for numerous applications.

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A newly developed portable x‐ray fluorescence spectrometer has been evaluated through the onsite and nondestructive analyses of 109 Roman glass artifacts excavated at a Roman cemetery found in Zadar, Croatia. The spectrometer has been designed for on‐site analysis of archaeological glass objects. The instrument consists of an x‐ray tube with a Pd target operated at up to 40 kV, silicon drift detector (SDD) with a polymer window, and an enlargeable vacuum sampling chamber. With this system, quantitative analysis of the light elements such as Na and Mg that are important components of glass, as well as heavy trace elements, was successfully carried out. The obtained results evidenced the use of Natron as fluxing agent with alkali contents of 14–22 wt% Na2O, 0.5 wt% MgO and 1.2 wt% Al2O3. In addition, it was found that the differences in the use of Mn and/or Sb as decolorizing agent in colorless bell‐shaped flasks collected from 10 different localities along the coast of Croatia comparing with the same type flasks excavated from Zadar. Copyright © 2009 John Wiley & Sons, Ltd.