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A promising technology for renewable energy is energy piles used to heat and cool buildings. In this research, the effects of bio-cementation via microbially induced calcite precipitation (MICP) using mixed calcium and magnesium sources and the addition of fibres on the thermal conductivity of soil were investigated. Firstly, silica sand specimens were treated with cementation solutions containing different ratios of calcium chloride and magnesium chloride to achieve maximum thermal conductivity improvement. Three treatment cycles were provided, and the corresponding thermal conductivity was measured after each cycle. It was found that using 100% calcium chloride resulted in the highest thermal conductivity. This cementation solution was then used to treat bio-cemented soil samples containing fibres, including polyethylene, steel and glass fibres. The fibre contents used included 0.5%, 1.0% and 1.5% of the dry sand mass. The results show that the glass fibre samples yielded the highest thermal conductivity after three treatment cycles, and SEM imaging was used to support the findings. This research suggests that using MICP as a soil improvement technique can also improve the thermal conductivity of soil surrounding energy piles, which has high potential to effectively improve the efficiency of energy piles.

AbstractThe concept of a ‘just transition’ to a low‐carbon economy is firmly embedded in mainstream global discourses about mitigating climate change. Drawing on Karl Polanyi's political economy elaborated inThe Great Transformation, we interrogate the idea of a just transition and place it within its historical context. We address a major contradiction at the core of global energy transition debates: the rapid shift to low‐carbon energy‐systems will require increased extraction of minerals and metals. In doing so, we argue that extractive industries are energy and carbon‐intensive, and will enlarge and intensify social and ecological injustice. Our findings reveal the importance of understanding how the idea of a just transition is used, and by who, and the type of justice that underpins this concept. We demonstrate the need to ground just transition policies and programmes in a notion of justice as fairness.

Abstract For fast reactor design and analysis, our laboratory uses, amongst others, the ERANOS code system. Unfortunately, the publicly available version of ERANOS does not have the most recent nuclear data. Therefore, it was decided to implement an integrated processing system to generate cross sections libraries for the ECCO cell code, as well as covariance data. Cross sections are generated from the original ENDF files. For our purposes, it is important to ascertain that the ECCO cross section libraries are of adequate quality to allow design and analysis of advanced fast reactors in an academic context. In this paper, we present an analysis of the MZA/MZB benchmarks with nuclear data from JENDL-4.0, JEFF-3.1.2 and ENDF/B-VII.1. Results are that reactivity is generally well predicted, with an uncertainty of about 1% due to covariances of the nuclear data. Reaction rate ratios are satisfactorily calculated, as well as the flux spectrum and reaction rate traverses. Some problems remain: the magnitude of the void effect is not satisfactorily calculated, and reaction rate traverses are not always satisfactorily calculated. On the whole, the ECCO libraries are sufficient for design and analysis tasks in an academic context. For high-precision calculations, such as required for licensing tasks and detailed design calculations, data adjustment is still necessary as the “native” covariance data in the ENDF files is not accurate enough.

Societal relations in rural areas have entered into a new stage of adjustment over the past decade. However, the adjustment, which might bring about profound societal changes in countryside as well as in China as a whole, have not been paid much attention and very few studies have been conducted from the perspective of ecological resource crises. We use the case of a village as an example to show how water pollution, as one of the contributory factors, possibly affect the transition of clans and societal changes in Chinese villages. Through observation and interviews, we find that there is an apparent rise of “New Clanism” within clans, which gradually abandons the tradition of supremacy of clan interests and places family or individual interests at top priority. We also find that clan boundaries get increasingly obscure since the integrity of clans is undermined by the rise of new interest groups across clans, but the boundaries remain relatively clear due to the consistency (albeit incomplete) of clan interests. Some new clan élites and representatives of new interest groups get involved in village governance, which indicates that their goals have shifted from natural resources to social or political capital. The significance of our findings is that they provide not only a unique perspective for the interaction between society and resources, but also some new ideas for the future study of rural China at the environment-social interface.

Abstract In hot and humid climate such as in Japan and south east Asia, dehumidification in summer is really important for air conditioning. Temperature and humidity independent control (THIC) of air conditioning system can handle sensible heat and latent heat separately, and provide good indoor environment and achieve energy conservation. Desiccant air handling unit is one of the major solution for THIC of air conditioning system. It needs hot water to regenerate sorbent which absorbs moist in the air. Combined heat and power can supply hot water at almost constant temperature for desiccant air handling system and also contribute to the business continuity plan of commercial buildings. However, there are still uncertainties about the factors which affect energy performance of desiccant air handling unit and the optimum design and operations in hot and humid climate. The objectives of this paper are to prove factors which affect energy performance of desiccant air handling unit by measurement analysis and show optimum condition of the desiccant air handling unit under various room conditions by simulation. Measurement analysis shows that energy performance of desiccant air handling unit depends not only on the inlet air condition to dehumidification wheel but also on designed supply air humidity. Furthermore, simulation results show the optimum inlet air condition entering dehumidification wheel under various supply air absolute humidity which is determined by design room conditions. These results provide useful information of desiccant air handling unit during design and operation phase of buildings in hot and humid climate.

The effect of delta 9-tetrahydrocannabinol (delta 9-THC) and alcohol, singly and in combination, on divided attention performance was investigated in cannabis users and non-users who were matched for alcohol use. Both cannabis and alcohol produced decrements in central and peripheral signal detections. Drug and alcohol effects were greater for signal presentations in the periphery. Cannabis users were less impaired in peripheral signal detection than non-users while intoxicated by cannabis and/or alcohol. These findings suggest the development of tolerance and cross-tolerance in regular cannabis users and/or the ability to compensate for intoxication effects.

Since their inauguration in 2005, supertall residential skyscrapers have established themselves as a truly new, 21st century phenomenon. Their uniqueness spans the spectrum of critically important issues, ranging from discrete ways of conceptualization, production, and delivery, introduction of latest technologies, strict organizational and spatial rules and practices, all the way to various socio-cultural impacts, which include the peculiar, often invisible ways of cultural accommodation. This paper presents parts of a larger research project into this urbo-architectural type, focusing on the capacity of these skyscrapers to address numerous issues related to residential density, especially in fast-growing megacities. While a substantial number of research projects explore economic, architectural, engineering, and environmental attributes of these buildings by focusing on measurable aspects of their production and use, the holistic comparisons and qualitative elaboration of the significance of the residential supertall phenomenon are still lacking. This paper attempts to fill that gap and open a new approach into investigations of supertall residential skyscrapers. The starting position is that these are not simply bigger and taller, but fundamentally different urban artefacts, which have an untapped capacity to reach another kind of quality. Definition and recognition of that difference will enable us to better capitalize upon the qualities which it brings and help avoid the problems which it generates.