Hydrogenation curves

Fig. 10.4 Hydrogenation curves of catalytic NBD hydrogenations (each at least 2.0 mmol) with [Rh(Ph-/ -glup-OH)NBD]BF4 at varying catalyst concentrations (0.0025,...

An analysis of the hydrogenation curves shown in Figure 10.13 indicates, for those precatalysts with R=2-propyl, 3-pentyl and cyclopentyl, that they can be described quantitatively as first-order reactions. The comparison between experimental and calculated data (the latter being determined by least-squares regres-... 

Figure 7. The termodesorption of hydrogen curves (at P= 0,1 MPa) of ittrium hydrides before and after mechanical dispersion.

Fio. 14. Specific catalytic activity of oxides of metals of the fourth period in the exchange of molecular oxygon and oxidation of hydrogen. Curve I reaction of isotopic exchange of molecular oxygen curve II oxidation of hydrogen in the excess of oxygen. 

The hydrogenation curve of cinnamaldehyde depended on the type of catalyst. Note that hydrogenation properties of Ru/SiOz were different from the properties of ruthenium-... 

Fig. 5.12 Sum (SC) of cathodic oxygen, hydrogen, and water polarization curves of Fig. 5.11. Oxygen curve dominates above -300 mV (SHE) and hydrogen curve below-300 mV (SHE). Water reduction makes negligible contribution to the current density. pH = 1.Po2 =0.2 atm...

In deaerated 1 N H2SO4 (pH = 0.56), hydrogen-ion reduction is the cathodic reaction with the cathodic polarization curve intersecting the iron, nickel, and chromium curves in the active potential region. Hence, active corrosion occurs with hydrogen evolution, and the corrosion rates would be estimated by the intersections of the curves. The curves predict that the titanium will be passivated. However, the position ofthe cathodic hydrogen curve relative to the anodic curves for titanium and chromium indicates that if the exchange current density for the hydro-... 

Fig. 1. Comparison of hydrogenation curve for isobutylene and hydrogen adsorption curve vanadium oxide catalyst.

Fig. 6.3 Cyclohexene hydrogenation curve with the catalyst precursor Pt2(dba)3 dispersed in BMI.BF4 (a), BMI.PFs (b) and BMI.OTf (c) under 6atm constant hydrogen pressure at 75°C. Cyclohexene molar ratio/Pt2(dba)3 = 250 [89],...

The viscosity of hydrogen is more conventional in its behavior. In this case, liquid-phase viscosity data have been extrapolated [i -32] from close to atmospheric conditions to a critical-point condition in the coordinates of residual viscosity vs. density. Both papers report nearly identical results ( 30 x 10 g/cm-sec) for the critical-point viscosity. Brebach and Thodos indicate that this value should be increased to bring it more in line with their reduced correlations for other diatomic gases and give a final value of rjc =37.6 x 10 g/cm-sec. Values of viscosity for hydrogen from both sources, over the liquid range for which no data exist, lie very close to the hydrogen curve of Fig. 3. The data from these sources, however, extend to values for the critical viscosity which appear to be somewhat low (see Table IV). No comparable studies for deuterium and tritium have previously been made. 

The concept of the corrosion potential can also be illustrated in a Knear i -E plot. Figure 7 shows two curves representing the Butler-Volmer equation for the metal and hydrogen reactions. The pointat which the rate of metal dissolution equals the rate of hydrogen evolution is the potential at which the metal curve is as high above the potential axis as the hydrogen curve is below the axis. That distance is the corrosion rate. 

Fig. 70. Steady-state current-potential curves for the oxidation of hydrogen (curve 1) and hydrazine (curves 2 to 7) on platinized platinum at 24 °C.

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