scholarly journals Syngas production by bi-reforming methane on an Ni–K-promoted catalyst using hydrotalcites and filamentous carbon as a support material

RSC Advances ◽  
2020 ◽  
Vol 10 (36) ◽  
pp. 21158-21173
Author(s):  
Adelino F. Cunha ◽  
Sergio Morales-Torres ◽  
Luisa M. Pastrana-Martínez ◽  
António A. Martins ◽  
Teresa M. Mata ◽  
...  
Keyword(s):  
High Temperatures ◽  
Support Material ◽  
Support Structure ◽  
Syngas Production ◽  
Filamentous Carbon

A Ni phase dispersed in CO2 is used with a K promoter in the BRM. The LDH support structure collapses at high temperatures, inducing large Ni crystal sizes, and disfavoring activity. The catalyst is compensated by the K promoter, and the formation of an Mg–Al-spinel.

scholarly journals Correction: Syngas production by bi-reforming methane on an Ni–K-promoted catalyst using hydrotalcites and filamentous carbon as a support material

RSC Advances ◽  
2020 ◽  
Vol 10 (41) ◽  
pp. 24492-24492
Author(s):  
Adelino F. Cunha ◽  
Sergio Morales-Torres ◽  
Luisa M. Pastrana-Martínez ◽  
António A. Martins ◽  
Teresa M. Mata ◽  
...  
Keyword(s):  
Support Material ◽  
Syngas Production ◽  
Filamentous Carbon

Correction for ‘Syngas production by bi-reforming methane on an Ni–K-promoted catalyst using hydrotalcites and filamentous carbon as a support material’ by Adelino F. Cunha et al., RSC Adv., 2020, 10, 21158–21173, DOI: 10.1039/D0RA03264F.

Tolerance Representation for Mechanism Assemblies in Layered Manufacturing

1998 ◽  
Author(s):  
Sanjay Rajagopalan ◽  
Mark R. Cutkosky
Keyword(s):  
Layered Manufacturing ◽  
Manufacturing Processes ◽  
Support Material ◽  
Support Structure ◽  
Specific Instance ◽  
Internal Geometry ◽  
Multiple Materials ◽  
Manufacturing Tolerances ◽  
The Impact

Abstract By building parts up incrementally in layers or “compacts,” 3D layered manufacturing processes are capable of fabricating parts with complex internal geometry and multiple materials. Additionally, since parts are built fully embedded in a sacrificial support material, it is possible to fabricate fully assembled devices with multiple moving parts and mating/fitting surfaces (such as mechanisms). Given the method of manufacture, it becomes possible to provide designers of linkages with some flexibility in expressing constraints on the manufactured geometry of these parts. For example, designers now have the option of directly specifying the geometry of gaps and clearances with explicit tolerance assignments. In processes like Shape Deposition Manufacturing (SDM), these features are directly manifest in the geometry of the support structure. In many cases, it is these “shadow” features that most directly govern the behavior of the artifact being built. This paper explores the impact of in-situ manufacturing of assembled mechanisms on the tolerances required. Relaxation of the assemblability constraint is shown to result in looser manufacturing tolerances and better control over gap geometry for the specific instance of an isolated pin-joint.

Production of Syngas by Combination of CO2 Reforming and Partial Oxidation of CH4 over Ni/Al2O3 Catalysts in Fixed-bed Reactor

2010 ◽  
Vol 8 (1) ◽  
Author(s):  
Mohammad Zangouei ◽  
Abdolsamad Zarringhalam Moghaddam ◽  
Abdolhosein Razeghi ◽  
Mohammad Reza Omidkhah
Keyword(s):  
Partial Oxidation ◽  
Sol Gel ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Sem Images ◽  
Co2 Reforming ◽  
Syngas Production ◽  
Oxidation Of Methane ◽  
Filamentous Carbon ◽  
Diffraction Patterns

Ni/Al2O3 catalysts were synthesized by sol-gel method with various nickel loadings. Chemical and physical properties of the catalysts were characterized by XRD and TPR techniques. X-ray diffraction patterns showed no peaks due to NiO species. Temperature-programmed reduction (TPR) indicated that the nickel species mainly presented in NiAl2O4 phase. The effect of nickel loading on the catalytic activity of Ni/Al2O3 catalysts, selectivity of products, yield of hydrogen production and H2/CO ratio was investigated in the combination of dry reforming and partial oxidation of methane (DRPOM) reaction. The results indicated that these parameters are greatly dependent on the amount of nickel loading. The results also revealed that the catalyst with 20 percent nickel loading had the highest activity for syngas production after 270 min reaction on stream. The SEM images of spent catalysts showed the formation of filamentous carbon on the 20Ni/Al and 30Ni/Al catalysts.

Design and Construction of Plot 0 Wide-Span Cantilever Beam Support

2013 ◽  
Vol 743 ◽  
pp. 150-154
Author(s):  
Zhen Li ◽  
Ning Hui He
Keyword(s):  
Bearing Capacity ◽  
Cantilever Beam ◽  
Main Beam ◽  
Support Material ◽  
Support Structure ◽  
Construction Scheme ◽  
Design And Construction

This paper represents the introduction to the selection, construction scheme and design of No. 0 support material for the main beam of Jianyi Bridge in Fengcheng City, the computational check on the bearing capacity of the support structure through MIDAS/Civil V2006 Modeling, then the bearing capacity of all the members can meet the requirements.

Formation of filamentous carbon from paraformaldehyde under high temperatures and pressures

Carbon ◽  
1998 ◽  
Vol 36 (7-8) ◽  
pp. 937-942 ◽  
Author(s):  
Yury G. Gogotsi ◽  
Klaus G. Nickel
Keyword(s):  
High Temperatures ◽  
Filamentous Carbon

Pyrolytic carbon filaments and associated catalytic particles formed in steel tubes

1984 ◽  
Vol 42 ◽  
pp. 662-663
Author(s):  
Y. L. Chen ◽  
J. R. Bradley
Keyword(s):  
Stainless Steel ◽  
Carbon Steel ◽  
Catalyst Particle ◽  
Pyrolytic Carbon ◽  
Plain Carbon Steel ◽  
304 Stainless Steel ◽  
Hydrocarbon Gases ◽  
Steel Tubes ◽  
Filamentous Carbon ◽  
Carbon Filaments

Considerable effort has been directed toward an improved understanding of the production of the strong and stiff ∼ 1-20 μm diameter pyrolytic carbon fibers of the type reported by Koyama and, more recently, by Tibbetts. These macroscopic fibers are produced when pyrolytic carbon filaments (∼ 0.1 μm or less in diameter) are thickened by deposition of carbon during thermal decomposition of hydrocarbon gases. Each such precursor filament normally lengthens in association with an attached catalyst particle. The subject of filamentous carbon formation and much of the work on characterization of the catalyst particles have been reviewed thoroughly by Baker and Harris. However, identification of the catalyst particles remains a problem of continuing interest. The purpose of this work was to characterize the microstructure of the pyrolytic carbon filaments and the catalyst particles formed inside stainless steel and plain carbon steel tubes. For the present study, natural gas (∼; 97 % methane) was passed through type 304 stainless steel and SAE 1020 plain carbon steel tubes at 1240°K.

In situ REM imaging of surface processes on ceramic bulk crystals from 300 to 1670 K in a conventional TEM

1991 ◽  
Vol 49 ◽  
pp. 660-661
Author(s):  
Z. L. Wang ◽  
J. Bentley
Keyword(s):  
High Temperatures ◽  
Image Resolution ◽  
Atomic Processes ◽  
Crystal Surfaces ◽  
Beam Radiation ◽  
Surface Areas ◽  
Transmission Electron ◽  
Reflection Electron Microscopy ◽  
Gas Reactions

Studying the behavior of surfaces at high temperatures is of great importance for understanding the properties of ceramics and associated surface-gas reactions. Atomic processes occurring on bulk crystal surfaces at high temperatures can be recorded by reflection electron microscopy (REM) in a conventional transmission electron microscope (TEM) with relatively high resolution, because REM is especially sensitive to atomic-height steps.Improved REM image resolution with a FEG: Cleaved surfaces of a-alumina (012) exhibit atomic flatness with steps of height about 5 Å, determined by reference to a screw (or near screw) dislocation with a presumed Burgers vector of b = (1/3)<012> (see Fig. 1). Steps of heights less than about 0.8 Å can be clearly resolved only with a field emission gun (FEG) (Fig. 2). The small steps are formed by the surface oscillating between the closely packed O and Al stacking layers. The bands of dark contrast (Fig. 2b) are the result of beam radiation damage to surface areas initially terminated with O ions.

Sign in / Sign up

Export Citation Format

Share Document