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Abstract  

In the recent paper [1] the claim is made that a probabilistic version of a common fixed point theorem of Pant holds. We provide some examples to demonstrate that this claim is false unless some additional conditions are imposed. Our note is desired to complete the interesting results in the quoted paper.

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Abstract  

We discuss the probabilistic stability of the equation µ ∘ fη = f, by using the fixed point method.

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Abstract  

In the recent paper of this journal [7], a common fixed point theorem in G-complete fuzzy metric spaces under the t-norm Min was proved. We show that this theorem actually holds in more general situations.

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Abstract

The aim of this paper is to prove some common fixed point theorems under certain strict contractive conditions for mappings sharing the common property (E.A) in Menger spaces. As applications to our results, we obtain the corresponding common fixed point theorems under strict contraction in metric spaces. Thus, our results generalize many known results in Menger as well as metric spaces. Some related results are also derived besides presenting several illustrative examples.

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Reaction Kinetics, Mechanisms and Catalysis
Authors:
Viorel Chihaia
,
Karl Sohlberg
,
Monica Dan
,
Maria Mihet
,
Alexandru R. Biris
,
Petru Marginean
,
Valer Almasan
,
George Borodi
,
Fumiya Watanabe
,
Alexandru S. Biris
, and
Mihaela D. Lazar

Abstract

The effect of Ag (1 wt%) and Au (1 wt%) on the catalytic properties of Ni/Al2O3 (7 wt% Ni) for methane steam reforming (MSR) was studied in parallel with the effect of CeO2 (6 wt%) and La2O3 (6 wt%) addition. The addition of 1 wt% Ag to the alumina supported nickel catalyst drastically decreased its catalytic properties at temperatures lower than 600 °C, due to the blockage of metal catalytic centers by silver deposition. The addition of Au and CeO2 (La2O3) to the nickel catalyst improved the methane conversion, CO2 selectivity and hydrogen production at low reaction temperatures (t < 600 °C). At 700 °C under our working conditions, the additives have no important effect in hydrogen production by MSR. The best hydrogen production at low temperatures was obtained for Ni–Au/Al2O3, due to the higher CO2 selectivity, cumulated with slightly higher methane conversion in comparison with Ni/CeO2–Al2O3. At high temperature, Ni/CeO2–Al2O3 is stable for 48 h on stream. Ni–Au/Al2O3 and Ni–Ag/Al2O3 are mainly deactivated due to the temperature effect on Au and Ag nanoparticles and less through coke formation. On Ni/Al2O3 and Ni/La2O3–Al2O3, crystalline, graphitic carbon was deposited after 48 h of reaction leading to catalyst partial deactivation. On the Ni/CeO2–Al2O3 surface, a porous amorphous form of deposited carbon was found, which does not decrease its catalytic activity after 48 h of reaction.

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