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The interface between the head of the window and the wall represents one of the largest thermal bridges of a building and one of the areas with the highest risk of surface condensation and mould growth. This study is concerned with the reliability and accuracy of assessing this thermal bridge heat loss and surface temperature at the junction of a window with a specific steel lintel where the window frame itself is excluded from the thermal model. Four cases were modelled, covering the evolution of the construction details of this junction, following changes in British legislation in regards to U-values. They were assessed with HEAT2D software under the standard (simplified) method and a more detailed approach. The outputs revealed that replacing the window frame with an adiabatic surface during the modeling process (as per standard) underestimates the risks of mould growth or surface condensation (as per PartL1A 2010), especially if the window has a high U-value.

Abstract Efficient hydrogen production from water by photocatalysis under sunlight requires a significant improvement in light-harvesting capability. Zinc sulfide is a promising, inexpensive hydrogen generation photocatalyst, but in its pure, bulk form it is only active under ultra-violet light. Here, we show clear evidence of photoelectrochemical activity of ZnS thin films under visible-light irradiation without any co-catalysts, achieved through defect engineering. Fabrication of nanostructured ZnS under controlled conditions introduces defects, and hence intermediate electronic states within the band gap, which allow significant absorption of light at energies below the band gap energy of pure, bulk ZnS. The measured band gap of the ZnS thin films is ~2.4 eV, while the photocurrent density exceeds 1.5 mA/cm2 under visible-light irradiation (λ≥435 nm). This is the first measurement of such high photocurrents for undoped ZnS under visible light.

In this paper, we investigate how to apply industrial unmanned aerial vehicles (UAVs) for autonomous power line inspection in smart grid from an energy efficiency perspective. Firstly, the energy consumption minimization problem is formulated as a joint optimization problem, which involves both the large-timescale optimization and the small-timescale optimization. Then, the NP-hard joint optimization problem is transformed to a two- stage optimization problem based on energy consumption magnitude and optimization timescale differences. Next, the first-stage and second-stage problems are solved by exploring dynamic programming (DP) and auction matching, respectively. Finally, the proposed algorithm is verified based on realistic power grid topology. Simulation results demonstrate that the proposed scheme achieves significant energy consumption reduction.

Cocoa beans (Theobroma cacao L.) are the raw material for chocolate production. Fermentation of cocoa pulp by microorganisms is crucial for developing chocolate flavor precursors. Yeasts conduct an alcoholic fermentation within the bean pulp that is essential for the production of good quality beans, giving typical chocolate characters. However, the roles of bacteria such as lactic acid bacteria and acetic acid bacteria in contributing to the quality of cocoa bean and chocolate are not fully understood. Using controlled laboratory fermentations, this study investigated the contribution of lactic acid bacteria to cocoa bean fermentation. Cocoa beans were fermented under conditions where the growth of lactic acid bacteria was restricted by the use of nisin and lysozyme. The resultant microbial ecology, chemistry and chocolate quality of beans from these fermentations were compared with those of indigenous (control) fermentations. The yeasts Hanseniaspora guilliermondii, Pichia kudriavzevii, Kluyveromyces marxianus and Saccharomyces cerevisiae, the lactic acid bacteria Lactobacillus plantarum, Lactobacillus pentosus and Lactobacillus fermentum and the acetic acid bacteria Acetobacter pasteurianus and Gluconobacter frateurii were the major species found in control fermentations. In fermentations with the presence of nisin and lysozyme, the same species of yeasts and acetic acid bacteria grew but the growth of lactic acid bacteria was prevented or restricted. These beans underwent characteristic alcoholic fermentation where the utilization of sugars and the production of ethanol, organic acids and volatile compounds in the bean pulp and nibs were similar for beans fermented in the presence of lactic acid bacteria. Lactic acid was produced during both fermentations but more so when lactic acid bacteria grew. Beans fermented in the presence or absence of lactic acid bacteria were fully fermented, had similar shell weights and gave acceptable chocolates with no differences in sensory rankings. It was concluded that lactic acid bacteria may not be necessary for successful cocoa fermentation.

AbstractBackgroundResearch shows that the prevalence of substance use disorders among the prison population is high globally. Although prisons are highly controlled environments, access to drugs and other substances in prison remains a major problem. Yet, previous research is focussed mainly on the Western context, with the studies generally reporting on lifetime prevalence without reference to whether the disorders are manifest even within the controlled environment.AimsTo estimate the prevalence of substance use disorders evident while in prison in Ghana and associated risk indicators. For these purposes, substance use disorder was defined by any indication of dependency, or escalating use or socially problematic use during the 12 months of imprisonment prior to the interview.MethodsThe study involved 500 adults (443 men and 57 women) in a medium‐security prison in Ghana who had served at least 1 year of a prison sentence. Participants' alcohol use disorder was assessed separately from other substance use disorders which included cannabis, cocaine and other stimulants using the Mini International Neuropsychiatric Interview (MINI); it is a structured interview and diagnostic tool for major psychiatric and substance use disorders in DSM‐5 and ICD‐10.ResultsTwo percent of the 500 participants had used alcohol to the level of alcohol use disorder, and 6% had other substance use disorders in 12 months prior to interview and while in prison. Cannabis (4%) and stimulants (3%) were the most frequently reported substance use disorders. Logistic regression model estimates indicate that younger age, prior offending and alcohol use dependence were significantly associated with such disorders in prison.ConclusionIn spite of efforts to prevent substance use in prison, nearly one in 10 of these prisoners were using alcohol or illicit drugs to a level indicative of substance use disorders. Our findings suggest that prioritising brief assessment may help identify those in most need of clinical help to limit their alcohol and illicit substance use problems.

Cities are leading actions against climate change through global networks. More than 360 global cities announced during the 2015 Paris Climate Conference that the collective impact of their commitments will deliver over half of the world’s urban greenhouse gas emissions reductions by 2020. Previous studies on multi-city carbon footprint networks using sub-national, multi-region input-output (MRIO) modelling have identified additional opportunities for addressing the negative impacts of climate change through joint actions between cities within a country. However, similar links between city carbon footprints have not yet been studied across countries. In this study we focus on inter-city and inter-country carbon flows between two trading partners in a first attempt to address this gap. We construct a multi-scale, global MRIO model to describe a transnational city carbon footprint network among five Chinese megacities and the five largest Australian capital cities. First, we quantify city carbon footprints by sectors and regions. Based on the carbon map concept we show how local emissions reductions influence other regions’ carbon footprints. We then present a city emissions ’outsourcing hierarchy’ based on the balance of emissions embodied in intercity and international trade. The differences between cities and their position in the hierarchy emphasize the need for a bespoke treatment of their responsibilities towards climate change mitigation. Finally, we evaluate and discuss the potentially significant benefits of harmonising and aligning China’s carbon trading schemes with Australia’s cap and trade policy.

The surface passivation quality and the bulk lifetime of boron-doped p-type Czochralski silicon wafers were studied in response to dark annealing at 175 °C, using in situ effective lifetime measurements. We investigated non-fired and fired silicon nitride (SiN x ), aluminum oxide (AlO x ) capped with SiN x , and thermally-grown silicon oxide (SiO2). Modulation in surface passivation quality and bulk lifetime was detected only in cases where hydrogen is assumed to be released into the silicon wafer from the dielectric (AlO x /SiN x stack and fired SiN x layer). Interestingly, the degradation of both the surface and the bulk were followed by a recovery. It is also interesting to note that the changes in the surface and the bulk seem to be related, as the surface degradation starts when the initial bulk degradation ends. This study indicates a possible involvement of hydrogen in both the degradation and the recovery processes. The evolution of the effective lifetime as a function of time is similar to that reported for carrier-induced degradation in multicrystalline wafers; however, occurring on a different time scale. Hence, these findings may also be valuable for investigation of other degradation mechanisms in different silicon materials.

Abstract Unburned carbon (UC) in fly ash indicates inefficiency in combustion and may be an impediment to the beneficial use of fly ash or ash products in a variety of applications. The characteristics of the coal-derived UC are a function of the rank and type of the coal, as well as the size of the feed coal and the combustion conditions. At any coal rank, inertinite macerals are inherently more difficult to combust than the associated vitrinite, and some will have a tendency to appear in the fly ash more or less unchanged from their appearance in the feed coal. The nature of UCs resulting from vitrinite is dependent upon the coal rank. Low-rank huminite/vitrinite will tend to form an isotropic char; bituminous vitrinite will appear as isotropic and anisotropic cokes; and anthracite vitrinite, naturally anisotropic, is observed as partially combusted vitrinite fragments in the ash. The absorption of air entraining agents by UCs limits the use of high-UC fly ashes as a Portland cement substitute, with both standards organizations and regulatory bodies imposing limits on the acceptable UC concentrations. UC in fly ash can be used to adsorb organic compounds (such as phenols, dyes, herbicides, polychlorinated biphenyls, and petroleum constituents) and to capture trace elements (particularly Hg) from flue gas. UCs can also be used as sources of activated carbons, manufacture of graphite, and cokes in the metallurgical industry, as well as a source of carbon to feed back into the boiler. Beneficiation of fly ash to segregate relatively UC-free or UC-rich splits for beneficial re-use can be done by size classification, electrostatic separation, and froth flotation, as well as density separation, acid digestion, and incipient fluidization. Thermal processing may also be used to burn off the UC, leaving a relatively UC-free fly ash as the product.