Theoretical Study of the Role of a Metal–Cation Ensemble at the Oxide–Metal Boundary on CO Oxidation

The article presents the results of a theoretical study of the influence processes of the developed digital technologies and the activities of enterprises and organizations on the changing role of man in labor and their social improvement. The necessity of a balanced and consistent approach to create conditions for the use of digital technologies in practical activities and determining the con- sequences not only in enterprises and organizations, but also in the conscious behavior and social realities of all workers, without exception, is substantiated. The main directions of the development of digital technologies are determined, involving the wide participation of workers in their use in enterprises and organizations.

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The Role of La2O3 in Enhancement the Radiation Shielding Efficiency of the Tellurite Glasses: Monte-Carlo Simulation and Theoretical Study

Materials ◽

10.3390/ma14143913 ◽

2021 ◽

Vol 14 (14) ◽

pp. 3913

Author(s):

Aljawhara H. Almuqrin ◽

Mohamed Hanfi ◽

K. G. Mahmoud ◽

M. I. Sayyed ◽

Hanan Al-Ghamdi ◽

...

Keyword(s):

Monte Carlo Simulation ◽

Theoretical Study ◽

Radiation Shielding ◽

Photon Flux ◽

Transmission Factor ◽

Tellurite Glasses ◽

Attenuation Coefficients ◽

Binary Glass ◽

Buildup Factors

The radiation shielding competence was examined for a binary glass system xLa2O3 + (1 − x) TeO2 where x = 5, 7, 10, 15, and 20 mol% using MCNP-5 code. The linear attenuation coefficients (LACs) of the glasses were evaluated, and it was found that LT20 glass has the greatest LAC, while LT5 had the least LAC. The transmission factor (TF) of the glasses was evaluated against thicknesses at various selected energies and was observed to greatly decrease with increasing thickness; for example, at 1.332 MeV, the TF of the LT5 glass decreased from 0.76 to 0.25 as the thickness increased from 1 to 5 cm. The equivalent atomic number (Zeq) of the glasses gradually increased with increasing photon energy above 0.1 MeV, with the maximum values observed at around 1 MeV. The buildup factors were determined to evaluate the accumulation of photon flux, and it was found that the maximum values for both can be seen at around 0.8 MeV. This research concluded that LT20 has the greatest potential in radiation shielding applications out of the investigated glasses due to the glass having the most desirable parameters.

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Role of the divalent metal cation in the pyruvate oxidase reaction.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)34115-2 ◽

1982 ◽

Vol 257 (16) ◽

pp. 9605-9611

Author(s):

R Blake ◽

T A O'Brien ◽

R B Gennis ◽

L P Hager

Keyword(s):

Metal Cation ◽

Divalent Metal ◽

Pyruvate Oxidase ◽

Divalent Metal Cation ◽

Oxidase Reaction

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On the Role of Diffusion in the Oxidation of Fe, Ni, Co and the Fe-Sn Alloy by Calcium and Sodium Sulfates

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.258-260.63 ◽

2006 ◽

Vol 258-260 ◽

pp. 63-67

Author(s):

V.M. Chumarev ◽

V.P. Maryevich ◽

V.A. Shashmurin

Keyword(s):

Co Oxidation ◽

Chemical Reaction ◽

Diffusion Processes ◽

Transport Processes ◽

Diffusion Transport ◽

Sodium Sulfates ◽

Product Forms ◽

Kinetics Of ◽

Dominant Part

Diffusion processes play a dominant part in the macro kinetics of Fe, Ni and Co oxidation by calcium and sodium sulfates. Here, the reaction product forms a compact covering which spatially divides the reagents on the surface in the same way as in the oxidation and sulfidization of metals by oxygen and sulfur. Therefore, it is possible to assume in advance that interaction of metals with calcium and sodium sulfates will be determined not by the actual chemical reaction properly but by the diffusion transport processes.

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