Spectroscopy CITS

Fig. 15 a Schematic principle showing the metal ion array on a graphite surface b and c show the results of the locally resolved current-induced tunneling spectroscopy (CITS) measurements of a [2 x 2] Co and [3 x 3] Mn indicating the position and arrangement of the respective metal ions. Adapted from [150]... 

Current imaging tunneling spectroscopy (CITS) Electrochemical scanning tunneling microscopy (ESTM) Scanning noise microscopy (SNM)... 

Summary Iodine was inserted into the voids of crystalline microporous materials built from pure SiOz (zeosils), namely UTD-1 (DON), SSZ-24 (AFI), CIT-5 (CFI), and ITQ-4 (IFR), by vapor phase loading. All these hosts possess large pores. Their iodine insertion compounds exhibit characteristic colors. The properties of these compounds were further studied by powder X-ray diffraction, UV-Vis and Raman spectroscopy. It turned out that the insertion compounds of the large-pore zeosils are unstable when removed from a saturated iodine atmosphere, a property in which they differ from the iodine insertion compounds of medium-pore zeosils. This instability hampered the characterization of these substances. 

The X-Ray patterns as well as the Raman spectroscopy results point to the exclusive formation of Cc2(W04)3 with no detectable WOx crystallites on the PP-samples, as observed in the ease of TiO or Z1O2 [20, 22]. On these catalysts, the WO domains are well dispersed, leading to an increased interaction between Ce and W. The case of the CIT-samples is different the XPS and Raman results indicate the formation of successive layers of W-containing species that causes a dramatic decrease of the acidity compared to the PP-catalysts. 

Values are means ( standard deviation of the mean) of four experiments and were determined by integration and time correction of peaks of radioactivity from 13N in radioscans after electrophoresis at pH 9.2, in comparison with 13N02 or radioactivity added as determined by scintillation spectroscopy. Asp, i)ar-tate Glu, glutamate Gin, glutamine Cit, citrulline Ala, alanine Arg, arginine. 

C.N. Kastner, M. Prummer, B. Siek, A. Renn, U.P. Wild, P. Dimroth, The citrate carrier CitS probed by single moleeule fluorescence spectroscopy, Biophys. J. 84, 1651-1659 (2003)... 

Raman spectroscopy. All eleven fundamental vibrations expected for a pseudo-octahedral anion (18) of symmetry Cit, were observed and assigned. 

The formation of C(V)-Cit complexes is confirmed by UV-vis and EPR spectroscopy (signal at = 1-977 with four Cr hyperfine satellites (coupling constants 18.7 G) (Figure 4.18)). The complex formation fadhtates the reduction of Cr(V). The competition of Cr(VI) and Cr(V) species for reducing conducting band electrons and of Cr(V) and dtric add for valence band holes is... 

Cr(VI) reduction takes place through Cr(V) spedes, readily complexed by citrate and detected by EPR spectroscopy. Quantitative EPR determinations indicate that an important fraction (nearly 15%) of the reduced Cr(VI) is transformed to Cr(V)-Cit, which also undergoes a photocatalytic transformation. 

CITS current imaging tunnehng spectroscopy HT high temperature... 

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