Long term leachate evolution during flow-through leaching of a vault backfill (NRVB)

2012 ◽  
Vol 76 (8) ◽  
pp. 3023-3031 ◽  
Author(s):  
E. J. Butcher ◽  
J. Borwick ◽  
N. Collier ◽  
S. J. Williams
Keyword(s):  
Microstructural Analysis ◽  
Hydrated Lime ◽  
Deionized Water ◽  
Disposal Facility ◽  
Solid Specimen ◽  
Specimen Volume ◽  
Flexible Wall ◽  
Flow Through ◽  
The Uk

AbstractSome of the illustrative concepts for the disposal of intermediate-level waste in a geological disposal facility in the UK employ a cementitious backfill around the waste packages. The concept for higher strength rocks would use a highly alkaline backfill composed of Portland cement (now known as CEM I), hydrated lime and limestone flour, referred to as Nirex reference vault backfill (NRVB).This paper reports a study of the extensive leaching of cured NRVB in a range of generic leachant compositions (deionized water, 0.1 M and 1 M NaCl solutions) under flow-through conditions using a flexible wall permeameter. The experiments were designed to run for up to two years and to pass at least 1000 volumes of leachant (defined as the cumulative leachate volume produced/NRVB solid specimen volume) through the NRVB samples. Results for the pH evolution profiles of the leachates and the microstructural analysis of the unleached and leached samples are presented.

scholarly journals Development of a Generic Safety Narrative for a UK Geological Disposal Facility

2015 ◽  
Vol 79 (6) ◽  
pp. 1633-1640 ◽  
Author(s):  
L. Bailey
Keyword(s):  
Environmental Safety ◽  
System Safety ◽  
Geological Disposal ◽  
Disposal Facility ◽  
Safety Barriers ◽  
Safety Case ◽  
The Uk ◽  
Surface Environment

AbstractThe UK has published a generic Disposal System Safety Case for a geological disposal facility (NDA, 2010) and is planning to update this in 2016. However, it is a challenge to present a meaningful safety case when the location and hence the design of a geological disposal facility are not known. Consequently, this paper describes our aim to present a narrative, explaining how we can have confidence in the long-term safety of a geological disposal facility. This narrative is based on an understanding of the environmental safety functions of a geological disposal facility and the features, events and processes (FEPs) that support them. The highest level environmental safety functions required for a geological disposal facility are isolation and containment. By isolation we mean removal of the wastes from people and the surface environment. By containment we mean retaining the radioactivity from the wastes within various parts of the disposal facility for as long as required to achieve safety. Beneath these top-level environmental safety functions we have identified generic environmental safety functions associated with each of the key safety barriers within a geological disposal facility, namely: the wasteform, the container, the local buffer or backfill, the mass backfill (in the access tunnels and service ways), the plugs and seals and the geosphere. This paper discusses the application of environmental safety functions and FEPs to building a safety narrative and explains how it is proposed to use such an approach to develop a generic environmental safety case for the UK to provide confidence in the longterm safety of a geological disposal facility after it has been sealed and closed.

Framework for an environmental safety case for geological disposal in the UK

2012 ◽  
Vol 76 (8) ◽  
pp. 3457-3464 ◽  
Author(s):  
M. J. Poole ◽  
R. Kowe
Keyword(s):  
Environmental Safety ◽  
Approval Process ◽  
Site Specific ◽  
Geological Disposal ◽  
Disposal Facility ◽  
Safety Case ◽  
The Uk ◽  
A Site

AbstractThe implementation of a geological disposal facility requires the demonstration of confidence that such a facility would be safe during both the operational period and in the long-term after the closure of such a facility. The generic environmental safety case described in this paper is the vehicle used to demonstrate an understanding of environmental safety. It will be used to prepare a site-specific environmental safety case in due course. The approach taken will be consistent with a staged development and approval process, as advocated by the environmental regulators.

An overview of near-field evolution research in support of the UK geological disposal programme

2012 ◽  
Vol 76 (8) ◽  
pp. 2995-3001 ◽  
Author(s):  
T. M. Beattie ◽  
S. J. Williams
Keyword(s):  
Radioactive Waste ◽  
Host Rock ◽  
Near Field ◽  
Radioactive Decay ◽  
Geological Disposal ◽  
Nuclear Decommissioning ◽  
Disposal Facility ◽  
Engineered Barriers ◽  
The Uk

AbstractThe near field, together with the containment and isolation provided by the geosphere, contributes to the long-term safety provided by a geological disposal facility (GDF) after closure. The different engineered barriers can prevent or limit the release of radionuclides and their migration to the undisturbed host rock or geosphere and are expected to fulfil their post-closure safety functions for many thousands to hundreds of thousands of years. They will continue to contribute to containment after their eventual degradation when there would no longer be confidence that they would continue to fulfil all of their safety functions in their totality. By that time, significant radioactive decay will have occurred, substantially reducing the hazard associated with the wastes. Therefore, demonstration of long-term safety requires an understanding of the evolution of the engineered barriers and the consequences for the generic safety functions that the different barriers provide. This paper provides an overview of the research of the Nuclear Decommissioning Authority Radioactive Waste Management Directorate into the evolution of the near field of a GDF.

Using the Change4Life Disney Branded 10-minute Shake Ups During the COVID-19 ‘Lockdown’

2020 ◽  
Author(s):  
Emily Budzynski-Seymour ◽  
James Steele ◽  
Michelle Jones
Keyword(s):  
Perceived Exertion ◽  
Affective Responses ◽  
Online Resources ◽  
Future Research ◽  
Affective States ◽  
Perceived Effort ◽  
Qualitative Feedback ◽  
Bidirectional Relationship ◽  
The Uk

Physical activity (PA) is considered essential to overall health yet it is consistently reported that children are failing to meet the recommended levels. Due to the bidirectional relationship between affective states and PA, affective responses are a potential predictor to long term engagement. Since late March 2020 the UK government enforced ‘lockdown’ measures to help control the spread of Coronavirus (COVID-19); however, this has impacted children’s PA. Using online resources at home to support PA is now common. The primary aim of this research was to investigate the use of the Change4Life 10-minute Shake Ups to support PA by examining the effects of Disney branding upon children’s (n=32) post activity affective responses and perceived exertion. The secondary was to investigate the effect of the lockdown on PA habits. Children had similar positive affective responses and perceived effort to activities; however, branding was considered to be a key contributing factor based upon qualitative feedback from parents. Children’s PA levels dropped slightly since ‘lockdown’ was imposed; though online resources have been utilised to support PA. The use of immersive elements such as characters and narrative in PA sessions, as well as utilising online resources during ‘lockdown’ appear potentially promising for future research.

GA: Armani’s Giorgio Armani

2018 ◽  
Author(s):  
Paul Brooker ◽  
Margaret Hayward
Keyword(s):  
Final Section ◽  
The Body ◽  
Body Shop ◽  
The Third ◽  
Haute Couture ◽  
Fashion Designer ◽  
The Body Shop ◽  
The Uk ◽  
Career Woman

The Armani high-fashion example illustrates the importance of adaptive rational methods in his founding and developing of an iconic high-fashion firm. Armani adapted stylistically to fashion’s new times in the 1970–80s by creating a new style catering for the career woman. His stylistic adaptation is compared with that of another famous Italian fashion designer, Versace, who instead modernized haute couture fashion and created a succession of glamourous styles. Both leaders exploited the same opportunity but in different ways. The third section compares these leaders’ legacies in the 1990s–2000s and assesses from a long-term perspective how capably they had used adaptive rational methods. The final section shifts the focus from fashion to the cosmetics industry and from Italy to the UK. Anita Roddick used adaptive rational methods to establish The Body Shop corporation in the 1970s–80s. However, she then abandoned rational methods with dire results for her corporation in the 1990s.

scholarly journals Knowledge and attitudes towards concussion in UK-based male ice hockey players: A need for attitude change?

2019 ◽  
Vol 14 (2) ◽  
pp. 153-161 ◽  
Author(s):  
Sarah Hutchinson ◽  
Paul Ellison ◽  
Andrew Levy ◽  
David Marchant
Keyword(s):  
Attitude Change ◽  
Ice Hockey ◽  
Knowledge And Attitudes ◽  
Accurate Knowledge ◽  
Hockey Players ◽  
Sport Concussion ◽  
Concussion History ◽  
Concussion Knowledge ◽  
The Uk

Objective Concussion is a common injury in ice hockey, and previous research suggests some misconceptions and unsafe attitudes amongst players. The purpose of this study was to assess sport concussion knowledge, attitudes and the effect of sport concussion history in UK-based male ice hockey players across three levels of competition: professional, semi-professional and amateur. Methods Sixty-one participants across a number of UK ice hockey teams completed the Rosenbaum Concussion Knowledge and Attitudes Survey and reviewed a series of statements to assess knowledge (concussion knowledge index), attitudes (concussion attitude index) and misconceptions of concussion. Results Level of competition and concussion history had no significant effect on concussion knowledge index or concussion attitude index. A positive significant relationship exists between playing experience and concussion knowledge index and concussion attitude index. Statements identified common misconceptions and areas of accurate knowledge regarding concussion symptoms suggesting that male ice hockey players have a higher level knowledge compared to a sample of the UK general public. Playing experience was associated with increased knowledge and increasingly safe attitudes towards concussion. Conclusion Despite knowledge relating to loss of consciousness and correct management of symptoms being generally accurate, there are worryingly unsafe attitudes regarding aspects of concussion. Such attitudes may well pose significant threats to players’ safety and long-term health.

scholarly journals Long-Term Stability of Different Kinds of Gas Nanobubbles in Deionized and Salt Water

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1808
Author(s):  
Yali Zhou ◽  
Zhenyao Han ◽  
Chunlin He ◽  
Qin Feng ◽  
Kaituo Wang ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Bubble Size ◽  
Ostwald Ripening ◽  
Salt Water ◽  
Dlvo Theory ◽  
Deionized Water ◽  
Hydrodynamic Cavitation ◽  
Term Stability ◽  
Long Term Stability

Nanobubbles have many potential applications depending on their types. The long-term stability of different gas nanobubbles is necessary to be studied considering their applications. In the present study, five kinds of nanobubbles (N2, O2, Ar + 8%H2, air and CO2) in deionized water and a salt aqueous solution were prepared by the hydrodynamic cavitation method. The mean size and zeta potential of the nanobubbles were measured by a light scattering system, while the pH and Eh of the nanobubble suspensions were measured as a function of time. The nanobubble stability was predicted and discussed by the total potential energies between two bubbles by the extended Derjaguin–Landau–Verwey–Overbeek (DLVO) theory. The nanobubbles, except CO2, in deionized water showed a long-term stability for 60 days, while they were not stable in the 1 mM (milli mol/L) salt aqueous solution. During the 60 days, the bubble size gradually increased and decreased in deionized water. This size change was discussed by the Ostwald ripening effect coupled with the bubble interaction evaluated by the extended DLVO theory. On the other hand, CO2 nanobubbles in deionized water were not stable and disappeared after 5 days, while the CO2 nanobubbles in 1 mM of NaCl and CaCl2 aqueous solution became stable for 2 weeks. The floating and disappearing phenomena of nanobubbles were estimated and discussed by calculating the relationship between the terminal velocity of the floating bubble and bubble size.

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