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Abstract  

The active sites of hydrogen-exchanged Y zeolite (HY) and dealuminated (HDY) zeolites are investigated by TPD of carbon monoxide. Only the high temperature TPD spectra of CO (TM620-690C) were observed, meaning that CO molecules interact with very strong acid sites. The amounts of CO bonded on these sites are small (less than 1 molecule per unit cell). The strong influence of dealumination on the coverage degree is found. The calculated values for kinetic parameters indicate chemisorption of CO in the investigated systems (Edes240 kJ mol-1, A1011 s-1).

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Introduction Traditional co-citation analysis does not take into account the proximity of references co-cited by an article. Some references are cited within the same sentence, whereas other references may be cited in further

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Co-housing és városi fenntarthatóság

Piaci és közösségi többlakásos fejlesztések helyválasztása a fenntarthatóság tükrében

Építés - Építészettudomány
Authors: Szabó Julianna, Kissfazekas Kornélia, and Babos Annamária

.) Babos Annamária – Horogh Petra – K. Theisler Katalin : Co-housing. Példák Bécsben és a közösségi együttélés lehetoségei Budapesten . Utóirat. A Régi-Új Magyar Építőművészet melléklete 18 ( 2018 ) 101 . 69 – 76

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Invar® oxidation in CO2

Kinetics and mechanism of formation of a wüstite layer

Journal of Thermal Analysis and Calorimetry
Authors: S. Menecier, S. Valette, P. Denoirjean, and P. Lefort

when wüstite Fe 1− x O is formed [ 1 , 2 ] according to the reaction: 1 that requires a sample heating in CO/CO 2 mixtures or in pure CO 2 atmosphere. It was worth verifying if such a process could be applied to Invar ® . This alloy was

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Abstract  

The interactions of CO with a high specific surface area tin dioxide was investigated by FTIR spectroscopy and thermogravimetric analysis. FTIR study of CO interactions have shown that CO can adsorb on cus (coordinatively unsaturated sites) Sn4+ cation sites (band at 2201 cm-1). In addition, CO reacts with surface oxygen atoms. This leads to the partial reduction of SnO2 surface and to the formation of ionised oxygen vacancies together with the release of free electrons, which are responsible for the loss of transmission. Formed CO2 can chemisorb on specific surface sites: on basic sites to form carbonates species and on acidic sites (Sn4+-CO2 species) which is in competition with the formation of Sn4+-CO species. TG experiment have shown that the reduction of SnO2 by CO at 400°C occurs in two steps. First, the reduction of SnO2 surface, which is a quick phenomenon. This has allowed to evaluate that more than 12% of reducible surface oxygens can react with CO, essentially because of the presence of a large amount of surface hydroxyl groups. The second step of the reduction of SnO2 would be the progressive reduction of SnO2 bulk by the slow diffusion of oxygen atoms from the bulk to the surface.

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sulfided Mo [ 3 , 4 ], Ni–Mo [ 5 – 10 ], Co–Mo [ 11 – 18 ] unsupported catalysts and their alumina-supported forms. Some researchers have studied the atomic ratios of major elements on pre-reaction and post-reaction sulfided Ni–Mo catalyst and confirmed

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Clinical and Experimental Medical Journal
Authors: Godwins Okagbo Echejoh, Matthew N. Tanko, Agabus N. Manasseh, Stella Ogala-Echejoh, Barnabas Mandong, and Edith Okeke

2000 HIV-1 co infection in children hospitalized with tuberculosis in South Africa Int. J. Tuberc. Lung Dis. 4 448 – 454 . [20]. P. Eamranond E. Jaramillo 2001 Tuberculosis in children: reassessing the need for improved diagnosis in

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Orvosi Hetilap
Authors: Zoltán Sohajda, Ildikó Káldi, Magdolna Kiss, and Andrea Facskó

Assia, E. I., Rotenstreich, Y., Barequet, I. S., et al.: Experimental studies on nonpenetrating filtration surgery using the CO 2 laser. Graefes Arch. Exp. Ophthalmol., 2007, 245 (6

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9 481 – 497 . GlÄnzel , W. 2001 National characteristics in international scientific co-authorship relations Scientometrics

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, PEMFCs require hydrogen feed that is mostly free from CO (<10 ppm), as otherwise the Pt based anode catalyst would be deactivated rapidly [ 2 , 3 ]. However, typical gas mixtures that are produced from steam reforming or autothermal reforming contain CO

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