Activity and coke formation of nickel and nickel carbide in dry reforming: A deactivation scheme from density functional theory

Dry reforming is a promising reaction to utilise the greenhouse gases CO2 and CH4. Nickel-based catalysts are the most popular catalysts for the reaction, and the coke formation on the catalysts is the main obstacle to the commercialisation of dry reforming. In this study, the whole reaction network of dry reformation on both flat and stepped nickel catalysts (Ni(111) and Ni(211)) as well as nickel carbide (flat: Ni3C(001); stepped: Ni3C(111)) is investigated using density functional theory calculations. The overall reaction energy profiles in the free energy landscape are obtained, and kinetic analyses are utilised to evaluate the activity of the four surfaces. By careful examination of our results, we find the following regarding the activity: (i) flat surfaces are more active than stepped surfaces for the dry reforming and (ii) metallic nickel catalysts are more active than those of nickel carbide, and therefore, the phase transformation from nickel to nickel carbide will reduce the activity. With respect to the coke formation, the following is found: (i) the coke formation probability can be measured by the rate ratio of CH oxidation pathway to C oxidation pathway (r(CH)/r(C)) and the barrier of CO dissociation, (ii) on Ni(111), the coke is unlikely to form, and (iii) the coke formations on the stepped surfaces of both nickel and nickel carbide can readily occur. A deactivation scheme, using which experimental results can be rationalised, is proposed. 

Co-tape casting fabrication, field assistant sintering and evaluation of a coke resistant La0.2Sr0.7TiO3-Ni/YSZ functional gradient anode supported solid oxide fuel cell

The ability to directly utilize hydrocarbons and other renewable liquid fuels is one of the most important issues affecting the large scale deployment of solid oxide fuel cells (SOFCs). Herein we designed La_0.2Sr_0.7TiO₃-Ni/YSZ functional gradient anode (FGA) supported SOFCs, prepared with a co-tape casting method and sintered using the field assisted sintering technique (FAST). Through SEM observations, it was confirmed that the FGA structure was achieved and well maintained after the FAST process. Distortion and delamination which usually results after conventional sintering was successfully avoided. The La_0.2Sr_0.7TiO₃-Ni/YSZ FGA supported SOFCs showed a maximum power density of 600mWcm^-2 at 750°C, and was stable for 70h in CH₄. No carbon deposition was detected using Raman spectroscopy. These results confirm the potential coke resistance of La_0.2Sr_0.7TiO₃-Ni/YSZ FGA supported SOFCs.

Sir Robert Hart Photo Collection on Flickr

The photographs in this album were selected with the assistance of the Sir Robert Hart Research Project, which is a collaboration between Special Collections & Archives in the Library, the School of Modern History & Anthropology, Queen’s University Belfast, and the Institute of Modern History at the Chinese Academy of Social Sciences (CASS) in Beijing. The research project is creating an annotated photobook from the Sir Robert Hart Photo Collection (originally donated in the 1970s) and the Irons Collection. The photographs here reflect those that will be included in the book.

Plat survey of Edward Burch's land

This document is a plat survey of Edward Burch, O. H. Spencer, Alex Powe, and Ann Spencer land.

Sir John Dering due date card

This is a due date card for the book titled Sir John Dering, with stamped dates from 1939-1940.

Animism in Rainforest and Tundra: Personhood, Animals, Plants and Things in Contemporary Amazonia and Siberia (Book Review)

Animism is a form of traditional spiritual belief that receives welcome treatment here. The observations of Victorian ethnologist travellers on the local peoples they regarded as primitive was analysed by Sir Edward (E. B.) Tylor, in Primitive Culture (1871) which established the working definition of animism followed by later generations of scholars. This came from the observation that non-scientific people did not always draw sharp distinctions between human persons and other entities such as animals, trees and even rocks but imbued these with soul. The latin anima, ‘soul, spirit’ provided the title of what was assumed to be a primitive religion, animism. The study being reviewed recognizes apparent connections within deep history between Siberia and the Amazon, and uses contemporary social anthropology to clarify assumptions about animism. This book on animism in two shamanic cultures explores personhood and the relations in pre-scientific human thought between humans and non-humans, in contexts where non-humans can be regarded as social persons (p.2).