Industrially relevant characterization of multi-walled carbon nanotubes (MWCNT) is still a challenging task. The aim of this work is to show novel and fast concepts for the chemical characterization of carbon nanotubes (CNT) by a combination of analytical techniques. Information obtained by individual tools like Fourier transform infrared spectroscopy (FTIR), attenuated total reflection infrared spectroscopy or Raman spectroscopy is not providing a full picture of the functionalization of MWCNTs. However, a combination of tools such as FTIR or mass spectrometry with thermogravimetric methods proved to be very useful. Sample preparation for FTIR and Raman spectroscopy is another focus of this contribution because of its strong effect on the results obtained. We also are suggesting methods for sample preparation that lead to highly reproducibility results. Measurements have been carried out on typical CNT samples such as commercially available pristine, carboxylated and amino-functionalized MWCNTs, and on polystyrenegrafted MWCNTs. The results may serve as a guidance for the qualitative and quantitative characterization of CNT.
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3D-TGA-FTIR image of amine functionalized MWCNT with relating TGA curve 相似文献
Light, GSH, action! Glutathione (GSH) fulfills a universal role as redox factor, scavenger of reactive oxygen species, and as an essential substrate in the conjugation, detoxification, and reduction reactions catalyzed by glutathione S-transferase (GST). A photoactivatable glutathione allows the GSH-GST network to be triggered by light. GST fusion proteins can be assembled in situ at variable density and structures by laser-scanning activation. 相似文献
A new neptunium(V) borate, K[(NpO(2))B(10)O(14)(OH)(4)], was synthesized using boric acid as a reactive flux. The compound possesses a layered structure in which Np(V) resides in triangular holes, creating a hexagonal-bipyramidal environment around neptunium. This compound is unusual in that it exhibits the Alexandrite effect, a property that is typically restricted to neptunium(IV) compounds. 相似文献
The formation of integral asymmetric membranes from ABC triblock terpolymers by non‐solvent‐induced phase separation is shown. They are compared with the AB diblock copolymer precursors. Triblock terpolymers of polystyrene‐block‐poly(2‐vinylpyridine)‐block‐poly(ethylene oxide) (PS‐b‐P2VP‐b‐PEO) with two compositions are investigated. The third block supports the formation of a membrane in a case, where the corresponding diblock copolymer does not form a good membrane. In addition, the hydrophilicity is increased by the third block and due to the hydroxyl group the possibility of post‐functionalization is given. The morphologies are imaged by scanning electron microscopy. The influence of the PEO on the membrane properties is analyzed by water flux, retention, and dynamic contact angle measurements.
We are going to perform an inclusive spectroscopy experiment of η′ mesic nuclei with the 12C(p,d) reaction to study in-medium properties of the η′ meson. In nuclear medium, the η′ meson mass may be reduced due to partial restoration of chiral symmetry. In case of sufficiently large mass reduction and small absorption width of η′ at normal nuclear density, peak structures of η′ mesic states in 11C will be observed near the η′ emission threshold even in an inclusive spectrum. The experiment will be carried out at GSI with proton beam supplied by SIS using FRS as a spectrometer. The detail of the experiment is described. 相似文献
We demonstrate screen printing of polymer waveguides on rigid and flexible substrates. The waveguides are characterized by optical microscopy and propagation losses are determined by cut-back measurements. Furthermore, the efficiency of light coupling using fluorescent molecules within the waveguides is measured with regard to the application feasibility in sensor systems. It is shown that minimum propagation losses of 0.74 dB/cm can be reached with this low-cost printing technique. 相似文献
Here for the first time we describe the use of high resolution nanoprobe X-ray fluorescence (XRF) mapping for the analysis of artists’ paints, hierarchically complex materials typically composed of binder, pigments, fillers, and other additives. The work undertaken at the nanoprobe sought to obtain highly spatially resolved, highly sensitive mapping of metal impurities (Pb, Cd, Fe, and other metals) in submicron particles of zinc oxide pigments used in early 20th century artists’ tube paints and enamel paints, with particular emphasis on Ripolin, a popular brand of French house paint used extensively by Pablo Picasso and some of his contemporaries. Analysis revealed that the Zn oxide particles only contain a little Fe, proving that the highest quality Zn oxide pigment, free of Pb and Cd, was used for Ripolin house paints as well as artists’ paints. Nanoprobe XRF mapping also demonstrated that artists’ tube paints generally have more abundant fillers and additional whites (based on Pb, Ti, Ca) than Ripolin paints, which contain mostly pure zinc oxide. The chemical characterization of paints at the nanoscale opens the path to a better understanding of their fabrication and chemical reactivity. 相似文献