scholarly journals Restraining deactivation of hierarchical zeolite supported NiW catalysts in the HDS of thiophene

RSC Advances ◽  
2015 ◽  
Vol 5 (90) ◽  
pp. 74150-74158 ◽  
Author(s):  
Y. Wang ◽  
C. Lancelot ◽  
C. Lamonier ◽  
M. Yang ◽  
Y. Sun ◽  
...  
Keyword(s):  
Mechanical Mixture ◽  
Hierarchical Zeolite ◽  
Thiophene Hds ◽  
Hierarchical Beta ◽  
Catalytic Performances

Improvement of the catalytic performances in thiophene HDS on NiW sulfides catalysts supported on commercial Beta (NiW/HB) and hierarchical Beta (NiW/HB-M) were studied by mechanical mixture with γ-Al2O3 (NiW/Al2O3) or Na+-exchange of the zeolites.

Structure and properties of gas-dynamic coatings and evaluation of their use in sliding friction pairs

2020 ◽  
pp. 260-266
Author(s):  
V.E. Arkhipov ◽  
T.I. Murav’eva ◽  
M.S. Pugachev ◽  
O.O. Shcherbakova
Keyword(s):  
Aluminum Oxide ◽  
Sliding Friction ◽  
Metal Layer ◽  
Structural Phase ◽  
Mechanical Mixture ◽  
Structural Factors ◽  
Coating Structure ◽  
Corundum Structure ◽  
Deposited Metal ◽  
Copper Zinc

The problems of changes in the coating structure depending on the composition of the sprayed mechanical mixture using copper particles and mixture of copper and zinc particles (" brass") and the effect of structural factors on the tribological properties of the deposited metal layer are considered. The results of X-ray structural, phase, chemical and durometric analyzes, as well as tribological testing of coatings are presented. It is found that structure with hardness of ≈102.7 HV is formed in the coating from mechanical mixture of particles of copper and aluminum oxide (corundum). Numerous pores are observed in the structure of the deposited metal layer, the main size of which does not exceed 2 μm. In the coating from mechanical mixture of particles copper, zinc and aluminum oxide (corundum), structure is formed based on copper with hardness of ≈106.5 HV, zinc — ≈49.7 HV, intermetallic compounds (γ- and ε-phases) — ≈168.7 HV, the mass fraction of which is 62.0, 7.9 and 24.2 %, respectively. Both coatings can be used in sliding friction pairs.

scholarly journals Understanding the Fundamentals of Microporosity Upgrading in Zeolites: Increasing Diffusion and Catalytic Performances

2021 ◽  
pp. 2100001
Author(s):  
Zhengxing Qin ◽  
Shu Zeng ◽  
Georgian Melinte ◽  
Tomáš Bučko ◽  
Michael Badawi ◽  
...  
Keyword(s):  
Catalytic Performances

scholarly journals Catalytic cracking of jatropha oil into biofuel over hierarchical zeolite supported NiMo catalyst

2021 ◽  
Author(s):  
Isalmi Aziz ◽  
Tri Retnaningsih ◽  
Dhika Gustama ◽  
Nanda Saridewi ◽  
Lisa Adhani ◽  
...  
Keyword(s):  
Catalytic Cracking ◽  
Jatropha Oil ◽  
Hierarchical Zeolite ◽  
Nimo Catalyst

scholarly journals Catalytic Antioxidant Activity of Bis-Aniline-Derived Diselenides as GPx Mimics

Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4446
Author(s):  
Giancarlo V. Botteselle ◽  
Welman C. Elias ◽  
Luana Bettanin ◽  
Rômulo F. S. Canto ◽  
Drielly N. O. Salin ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Hydrogen Bond ◽  
Electronic Properties ◽  
Partial Charge ◽  
Amino Group ◽  
Diphenyl Diselenide ◽  
Charge Delocalization ◽  
Ipso Substitution ◽  
Efficient Route ◽  
Catalytic Performances

Herein, we describe a simple and efficient route to access aniline-derived diselenides and evaluate their antioxidant/GPx-mimetic properties. The diselenides were obtained in good yields via ipso-substitution/reduction from the readily available 2-nitroaromatic halides (Cl, Br, I). These diselenides present GPx-mimetic properties, showing better antioxidant activity than the standard GPx-mimetic compounds, ebselen and diphenyl diselenide. DFT analysis demonstrated that the electronic properties of the substituents determine the charge delocalization and the partial charge on selenium, which correlate with the catalytic performances. The amino group concurs in the stabilization of the selenolate intermediate through a hydrogen bond with the selenium.

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