Synergetic promotion

Low-temperature activity promotion is an issue in mobile (diesel) applications, but may not be a critical issue in several stationary applications, apart from those where the temperature of the emissions to be treated is below 200°C (for example, when a retrofitting SCR process must be located downstream from secondary exchangers, or in the tail gas of expanders in a nitric acid plant). In the latter cases, a plasmacatalytic process [91] could be interesting. In the other cases, the use of NTP together with the SCR catalyst is not economically viable. However, the synergetic combination of plasma and catalysts has been shown to significantly promote the conversion of hazardous chemicals such as dioxins [92], Although this field has not yet been explored, it may be considered as a new plasmacatalytic SCR process for the combined elimination of NO, CO and dioxins in the emissions from incinerators. 

Synergetic promotion Here the support interacts energetically with the catalyst and produces a new kind of active entity. 

Phenomenologically, synergetic promotion is characterized by an increased reaction rate, accompanied by a decreased activation energy, compared with the catalyst alone. Structural promotion, on the other... 

It was shown [21] that polyelectrolytes having hydrophobic functionalities show higher efficiency for such systems due to the synergetic effect of electrostatic and hydrophobic interactions promoting the polymer adsorption at solid/liquid or liquid/hquid interface. 

The effects of compositions and reaction conditions on product distribution were investigated over various metal promoted Cu-based catalysts to improve the performance for synthesis of hydrocarbons. The formation of carbon monoxide was suppressed and the formation of hydrocarbons increased with the increase in the amount of Fe. The synergetic effect between copper and iron was required for hydrocarbon synthesis. 

Synergetic effects promoted by in operandi surface reconstructions of oxides... 

The compatibility of the barrier material and Cl carrier in the polymer films promotes their high Anticorrosive on characteristics of polymer inhibited films are promoted my synergetic actions of two factors barrier film property and IC specific action. 

WGS or OSC were often considered as the most significant effects. There is a high degree of synergetic interaction with noble metals (Pd, Pt, Rh) [63], which can lead to (i) the promotion of the bulk, and the reduction of the surface, with enhanced reactivity towards CO and NO (ii) an enhanced exchange rate between oxygen from the bulk and reactants from the gas phase, and (iii) an enhanced dispersion of the metal. 

Quite interestingly and importantly, the synergism between Ce(IV) and Pr(III) described above (sect. 2.4) is also operating in these homogeneous solutions, and the catalytic activity of homogeneous Ce(lV)/dextran system was synergistically promoted by Pr(III). The activity for DNA hydrolysis shows a maximum at the [Ce(IV)]/[Pr(III)] ratio of 2. Other lanthanide ions also synergetically promoted the DNA hydrolysis by the Ce(TV)/dextran system. 

The first description of a synergetic effect due to a mixed cobalt-molybdenum catalyst (oxides and sulfides) was in 1933 by Pease and Keithon (11) at the Princeton University. Their catalytic system was active for the HDS of a mixture of benzene and thiophene. However, difficulty in reproducing their results already pointed out the complexity of this promotion effect, highly dependent on the conditions of preparation and pretreatment and the experimental conditions. 

The idea of introducing poly(vinyl alcohol) into nylon-6,6 composition is based on the possibility of high-temperature acid-catalyzed dehydration. This reaction can be provided by the acid products of nylon 6,6 degradation hydrolysis which would promote the formation of intermolecular crosslinking and char. Such a system we have called "synergetic carbonization", because the char yield and flame suppression parameters of the polymer blend of poly (vinyl alcohol) and nylon 6,6 are significantly better than that of pure poly(vinyl alcohol) and nylon-6,6 polymers. 

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