Atmospheric hydrocarbons from solvents, pump oils, and vacuum greases containing long-chain hydrocarbons are common contaminants, especially because of their affinity towards graphene. While XPS is a sensitive surface characterization technique, contamination of the sample by hydrocarbons is the biggest challenge. (B) Identification of percentage composition of carbon bonding in the same sample C1 is C C, C2 is C O, and C3 is C O carbon species. (A) XPS spectra of graphene exfoliated in organic solvent using a kitchen blender in comparison to that of graphite, which shows the absence of significant oxidation of the sample during exfoliation. Atomic percentage values and elemental ratios were calculated from the peak-area ratios after correction with the experimentally determined sensitivity factors, being reliable within ± 10%.įigure 3.7. XPS data were also used to examine the atomic composition and surface species of initial and modified polymer. This peak-fitting was repeated until an acceptable fit was obtained. Curve fitting was performed using the nonlinear list-squares algorithm and assuming a mixed Gaussian/Lorentzian peak shape of variable proportion. Data processing was performed according to ECLIPSE program, applying Schirley-type background subtraction. Each spectral region was scanned between 10 and 20 times depending on the signal intensity. Survey scans were collected from 0 to 1200 eV with pass energy of 50 eV for each sample followed by the regions C1s, N1s, and O1s. The X-ray gun was operated at 15 kV and 20 mA. The measurements were performed at base pressure lower than 8 XPS spectra were obtained by means of ESCALAB-210 electron spectrometer (VG Scientific Ltd., Sussex, U.K.), employing mg Kα X-rays. Goworek, in Studies in Surface Science and Catalysis, 2002 2.2.1 XPS measurements The change in chemical environment contributes to the observed shift in peak positions and intensities.Ī. These peaks of carbon-containing oxygen for DPPES–GNO are slightly shifted from those in the spectrum of pure GNO, owing to the strong chemical interaction between DPPES molecules and GNO. 11.5(c) that correspond to C–P at 286.1 eV 28,38 and C–Si at 284.0 eV 3,46 verify the grafting reaction of DPPES on GNO. DPPES–GNO exhibits similar oxygen functionalities, but with much lower peak intensities than those of GNO. 11.5(b) shows significantly stronger signals than that of GNs, indicating effective oxidation of GNs after the chemical reaction. The main peaks of C1s at 284.3 and 284.7 eV are attributed to the sp2 carbon of C C bonding and the sp3 carbon of C–C in the graphitic structure, whereas the four peaks at 288.5, 287.1, 286.5, and 285.3 eV are attributed to the carbon atoms in the O–C O, C O, C–O–C, and C–OH functional groups, respectively, 15,41,47 as displayed in Fig. The C1s spectrum of GNs includes three peaks that are attributed to the oxygen-containing functional groups, hydroxyl, epoxy, and carbonyl. 11.5 displays the C1s peaks of GNs, GNO, and DPPES–GNO. It can provide useful information on the nature of the functional groups and the functionalization of GNO.
The back design consists of two aluminum struts that offer high stability and guarantee great comfort, even when the backpack is heavily loaded.XPS is a method for analyzing the surface of a material.
#Xps peak 28ev full
The full contact back fits closely to the body and offers optimum weight distribution. A further advantage of wool is that the surface of the back system dries faster. Thanks to the wool, the back of the backpack can absorb almost 30 times more moisture than a comparable back made from foam and is almost 7 % more breathable. As with the clothing, mountaineers benefit from the wool’s unique moisture and microclimate management, making it feel comfortable and dry on the back. What makes this backpack so special is the back system made from pressed Swiss wool.
This backpack is also hydration system compatible and includes images of Alpine emergency signals. The PEAK 32 S also scores highly with a separate safety compartment, attachment options for rope, ice axe and crampons, as well as a separate map compartment and a hip pocket. A circumferential front zipper enables direct access to the main compartment. The broad, padded shoulder and hip straps distribute the weight of the load evenly between the shoulders and hips, ensuring a high level of wear comfort. This alpine tour backpack is very robust thanks to the use of the extremely tear and abrasion resistant material Nylon 420D Manstar. The back system of this backpack is significantly shorter. The PEAK 32 S is a backpack for Alpine activities that has been adapted especially for mountaineers with a short back – the “S” in the name stands for SHORT.