R, TPr

However, all the well known techniques of physical analysis are indispensable for the study of the catalysts. XPS-UPS, ISS, AES, STEM, diffuse reflectance, Mossbauer, n.m.r., TPR-TPD, etc., are already largely used and their contribution to these studies is obvious. EXAFS could in the near future provide valuable new information, because of the possibility of determining... 

The undoubtedly structure-sensitive reaction NO -r CO has a rate that varies with rhodium surface structure. A temperature-programmed analysis (Fig. 10.8) gives a good impression of the individual reaction steps CO and NO adsorbed in relatively similar amounts on Rh(lll) and Rh(lOO) give rise to the evolution of CO, CO2, and N2, whereas desorption of NO is not observed at these coverages. Hence, the TPRS experiment of Fig. 10.8 suggests the following elementary steps ... 

Reasonable NO conversion can be achieved using n-decane as reductant. In the absence of sulfur dioxide, the catalytic activity is roughly related to the r ucibility of the Cu phase of Cu ions in zeolites the reaction temperature needed to reach 20% NO conversion parallels that of the TPR peak (Table 7). This relation also practically holds for Cu on simple oxides, therefore a redox mechanism in which reduction of Cu + cations is the slow step could account for the results. 

Figure 9.7 Temperature-programmed reaction (TPR) spectra for CO oxidation at a series of model catalysts prepared by the soft landing of mass-selected Aun and AunSr cluster ions on MgO(lOO) thin films which are vacancy free (typically 1 % of a monolayer), (a) MgO (b) Au3Sr (c) Au4 (d) Au8. Also shown is the chemical reactivity R of pure Aun and AunSr clusters with 1 < n < 9. (Reproduced from Ref. 21).

Notes CO cardiac output VR venous return HR heart rate SV stroke volume EDV end-diastolic volume ESV end-systolic volume O blood flow AP pressure gradient R resistance r vessel radius P systolic pressure Piiastoik- diastolic pressure MAP mean arterial pressure TPR total peripheral resistance, P venous pressure Era- right atrial pressure Rv venous resistance. 

Van t Blik H.F.J. and Prins R. 1986. Characterisation of supported cobalt and cobalt-rhodium catalysts. 1. Temperature-programmed reduction (TPR) and oxidation (TPO) of Co-Rh/Al203. J. Catal. 97 188-99. 

Figure 6 Cyclic voltammogram recorded at a platinum electrode in a CH2Cl2 solution of [Fe11 (r 5-C5H5)Fe(r 5-C5H4(TpR) 2] (R — SiMe3). Scan rate 0.2 V s ...

Leanza, R Rossetti, 1 Fabbrini, L Oliva, C Fomi, L. Perovskite catalysts for the catalytic flameless combustion of methane Preparation by flame-hydrolysis and charaeterisation by TPD-TPR-MS and EPR. Appl. Catal, B Environmental, 2000, Volume 28, Issue 1, 55-64. 

The authors wish to acknowledge the invaluable assistance of S. M. Kuznicki who conducted the hydrocarbon adsorption experiments, D. R. Anderson who ran and assisted in the interpretation of the TPR, and H. Furbeck who prepared the many samples tested. 

Scheme 2.5 Ligands used to synthesize structural and/or functional models for iron enzymes containing a 2-His-l-carboxylate facial triad (a) R3TACN (TACN = 1,4,7-triazacyclononane) [25] (b) TpR,R [differently substituted hydridotris(pyrazol-l-yl)borates] [27] (c) differently substituted bis(pyrazol-l-yl)acetates [29] (d) differently substituted 3,3-bis(1 -alkylimidazol-2-yl)propionates [30],...

Main, E. R., Xiong, Y., Cocco, M. J., D Andrea, L., and Regan, L. (2003). Design of stable a-helical arrays from an idealized TPR motif. Structure 11, 497-508. 

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