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Thermal energy storage and fire safety of building materials
No full textEnergy storage using organic phase change materials (PCMs) has attracted significant attention in recent years for renewable energy utilization in building materials. PCMs are capable of storing and releasing a large amount of latent heat during their phase transitions.Paraffin (PA), a eutectic mixture (EM) of capric acid (CA) and lauric acid (LA) and butyl stearate (BS) have been selected as PCMs for this work due to their melting temperatures being close to human comfort temperature, 17 - 28 oC. Plaster (PL) as a building material is chosen due to its ease of construction into plaster boards and also because it is a good insulator against heat and sound. The most significant concern when using an organic PCM is its flammability. This research sets out to determine the effect of using PCMs in PL on the product’s flammability, and whether it is possible to use carrier materials and/or flame retardants to reduce their flammability while maintaining the thermal energy storage properties. Three techniques of incorporation of PCMs into PL are used to address this question. The first one is to immerse PL into hot melted PCMs using a vacuum impregnation method. The PCM however, could easily leak to the surface of PL, particularly when the temperature is above the melting temperature of PCM and also their high flammability evaluated using cone calorimetry was a limiting factor to pursuance of this route. The second method is a direct incorporation technique, i.e. adding PCM directly to PL. With this method also the leakage of PCMs was observed and all samples ignited, though the flammability parameters were less intense than those observed when the immersion method was used.To prevent the leakage of PCM and to improve the consistency of organic PCM with building materials, form-stable PCMs composites are used in the third method. Carrier materials, namely nanoclay (NC), diatomaceous earth (DE), expanded perlite (EP), fly ash (FA) and brick dust (BD) were selected to adsorb and retain the PCMs in their pores. SEM (scanning electron microscope) demonstrated that PCMs were uniformly adsorbed in most of the carrier materials. DSC (differential scanning calorimeter) used to measure the thermal properties of PCMs showed that when these form stable composites were added to PL, they acted as PCMs, although the latent heat values were reduced. Thermal gravimetric analysis (TGA) results demonstrates that the PCMs’ decomposition was not affected by the presence of carrier materials or PL. Cone calorimetry showed that the use of carrier materials had minimal effect on the flammability of PCMs. To evaluate the thermal energy storage performance, a small environmental chamber was used, i.e. a small test “room” of PL with dimensions of 100 mm x 100 mm x 100 mm and thickness 10 mm was set up using 6 pieces of PL. The top board of the cubic room contained PCM, and the temperature differences between the surfaces of control PL and modified PL were recorded during heating and cooling of the room. The results from heating and cooling cycles showed that the PCMs and form stable-PCM composites reduced the peak temperature and delayed the time taken to release the stored energy, the values depending on the percentage of PCMs used.To reduce the flammability of PCMs while maintaining their energy storage performance, two approaches have been undertaken: (i) use of expanded graphite (EG) as a flame retardant carrier- material and (ii) use of a liquid flame-retardant, resorcinol bis(diphenyl phosphate) (RDP). The results demonstrated that the flame retardant did not affect the energy storage performance of the PCM. While RDP was not effective on a PA containing PL sample, the flammability of a PL+BS sample was significantly reduced with the addition of EG and RDP
The legal conceptualisation of investment securities in the Nigerian Capital Market: challenges and opportunities
No full textTensions created by continuous disruption in the financial landscape leading to increased market convergence have suddenly rekindled the age long philosophical dispute between ‘form’ and ‘function’ as it relates to the conflict between indigenous and received legal traditions. This research tests these competing theories in the conceptualisation of securities. The formalist explanation considers the degree of institutional influence a sole reliance on legal texts play in achieving statutory coherence and utility; such as applying the strict interpretation of legal letters to reduce the uncertainties of contexts. By contrast, the functional explanation captures the limitation of legal texts without an examination of contexts. Therefore, statutory design and definition must seek to operationalise the outcomes of historical, political, economic, and socio-cultural contexts in its formation. This research raises the hypothesis that formalism places significant constraints on the language of statute to optimise products development, while functionalism enables the aggregation of legal and non-legal themes to create products. It goes further to tests these hypotheses on critical literature review and on a data set of regulatory agencies and market participants in Nigeria. It explores the conflicts created and how they continuously erode the underlying conceptual structure of securities. The research finds strong support for the functionalist context sensitive explanations. Therefore by developing and proposing a functional court-centred context-sensitive model as solution, this research suggests that formalist structure contributes to definitional incoherence of securities and places significant constraints on the capacity of language to optimise securities laws for increased product development in capital markets.The research further stresses the usefulness of real world semantics within language philosophy in shaping representionality of legal texts by providing a basis for the context sensitive conceptualisation. Through the use of focused group case study research technique, the thesis identified the legal obstacles to the conceptualisation of securities in the Nigerian Capital Market. It clarifies the place of negotiability, transferability and circularity components within the context of securities concepts of rights and duties. This is with a view to unearthing the legal nature of negotiable risk that sits at the core of securities. The research proposes a context sensitive definition of securities for the Nigerian Capital Market to replace the current definition in Section 315 of Investment and Securities Act 2007
Three stages of student engagement in a flipped-classroom environment. Appendix 2: Areas and Volumes
No full textAim: To present a simplified case of the interception of a line and a circle in order to support students’ understanding of more difficult examples.Preparedness = 0 X Number of Type 1 pages + 1 X Number of Type 2 pages + ½ X Number of Type 3 pages =
The compliance of Sukuk with Maqasid Al Sharia’a :A case study of the Medium Term Note Sukuk programme of the Islamic Development Bank
No full textThe ultimate aim of this thesis is to investigate the compliance of Sukuk (financial certificates or Sharia'a-compliant bonds) with Maqasid Al Sharia’a in hifth al mal, where the Islamic Development Bank’s (IDB) Medium Term Note (MTN) Sukuk Programme represents the case study for this research.To carry out this investigation, the researcher developed a theoretical framework through appraising the conceptions and theories of Maqasid Al Sharia’a, followed by a review to define human development in the context of Maqasid Al Sharia’a, which is directly connected to the concept of benefit (maslaha).The review is then developed to present the first model of Maqasid Al Sharia’a in hifth al mal. The thesis presents a conceptual understanding for Sukuk as an important tool for achieving human well-being and sustainable development, while keeping Maqasid Al Sharia’a in hifth al mal in perspective.The primary data were generated from elite interviews with senior experts and decision makers at the IDB, where their highly significant experience contributes to defining the criteria for the preservation of wealth according to Maqasid Al Sharia’a. From the Maqasid Al Sharia’a theories and the data generated from the interviews, a Maqasid Al Sharia’a model is developed, with this model then employed to analyse the completed IDB projects that were financed by the MTN Sukuk Programme in the 2007–2017 period.The general findings emerging from this research indicate that the MTN Sukuk Programme is serving the basic elements in the Maqasid Al Sharia’a model to a high degree, with considerable potential for the Programme to serve Maqasid Al Sharia’a in hifth al mal. The impact of the MTN Programme in the Maqasid Al Sharia’a model was found to be significantly positive in terms of achieving human well-being and sustainable development. Finally, it is concluded that applying Maqasid Al Sharia’a in hifth al mal to financial contracts will serve the Islamic purpose of promoting well-being and global development
Group Creative Engagement: Pure and applied digital stories based on this week's lecture.
No full text
The virtuous cyborg
No full text"Game deisgner and philosopher Chris Bateman explores cyborg virtue through problems such as cyberbullying, 'fake news' and the indifference of computers to human needs. Bateman reveals our shallow-sighteness in the face of the unfathomable complexity of our cybernetic networks. Critical yet optimistic, The Virtuous Cyborg rises to the challenge of the twenty-first century by asking us to ponder the question of what kind of cyborgs we want to become."-- Back cover.
Includes bibliographical references (pages 179-188)
Who am I and how did I get here? The development of professional identity through incidental learning, for trainee teachers in the FE sector.
No full textIt has been argued that teacher identity is shaped by the experiences that trainees have while in placement (Avalos, 2011; Jephcote, Salisbury, 2009). Through negotiation, collaboration and consolidation a trainee teacher is able to navigate the often turbulent landscape that exists in the Further Education and Skills sector (Orr, 2012). Incidental learning has been defined as unplanned and internally constructed through a process, prompted when an unexpected, serendipitous moment is experienced by an individual, often during a non-routine experience (Marsick and Watkins, 1992, Kerka, 2000; Polly, 2007). This makes it prevalent in learning environments, particularly for trainee teachers who are more likely to experience vast amounts of disjuncture.This paper explores the ideas around the development of trainee teachers’ professional identity for through the findings from a longitudinal study. A theoretical framework is presented and evaluated in terms of the data generated from a range of qualitative research methods. This research challenges the idea of criteria based professionalism, arguing instead for a more holistic development of professional identity, developed gradually through incidental learning. Initial teacher educators can use this framework to review and develop existing formal learning provision, identifying ways to supplement the development of professional identity within formal learning. Trainee teachers will be able to reflect on their own professional identity, professional relationships and self-evaluation strategies in order to engage with disjuncture in a way that will lead to improvement in their practice
