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Abstract This paper summarises studies undertaken towards the development of a laminated composite aluminium/hexadecane phase change material (PCM) drywall based on previous analytical work. The study also covered the selection and testing of various types of adhesive materials and identified Polyvinyl acetate (PVA) material as a suitable bonding material. For the purpose of comparison pure hexadecane and composite aluminium/hexadecane samples were developed and tested. The test results revealed faster thermal response by the aluminium/hexadecane sample regarding the rate of heat flux and also achieved about 10% and 15% heat transfer enhancements during the charging and discharging periods respectively. Its measured effective thermal conductivity also increased remarkably to 1.25 W/mK as compared with 0.15 W/mK for pure hexadecane. However there was about 5% less total cumulative thermal energy discharged at the end of the test which indicates that its effective thermal capacity was reduced by the presence of the aluminium particles. The study has shown that some of the scientific and technical barriers associated with the development of laminated composite PCM drywall systems can be overcome but further investigations of effects of adhesive materials are needed.

In the North-Central USA, switchgrass to be used as a biomass feedstock typically will be harvested in the autumn. The accumulated area harvested over the harvest season (defined here as the harvest progression) will influence the size of the machinery fleet and seasonal labor required to complete the majority of the harvest before the first lasting snow. A harvest progression model was developed that uses drying rate, mower and baler productivity, and weather conditions as major inputs. Ten years of weather data (2005–2014) from Wisconsin, Iowa, and Nebraska (WI, IA, NE) were used. Harvest progression was modeled for four harvest systems involving conventional and intensive conditioning both swathed and tedded (CC, IC, CCT, and ICT, respectively) and two dates at which harvest began (1 September and after a killing frost). To reduce risk of exposing crop to prolonged periods of inclement weather, mowers were idled when more than 80 ha were cut but not yet baled. For all sites, the harvest start date and the mower idled constraint had greater impact on harvest progression than the type of harvest system. Harvest progression was greatest when mowing started on 1 September and continued whenever weather permitted (i.e., no mower idled constraint). Compared to the harvest system used today (CC), using the IC system resulted in more area harvested with less crop exposed to rain after cutting and considerably less area left to be baled in the spring. Starting harvest on 1 September, using intensive conditioning, and not idling the mowers might be considered the system that best balances the desire for rapid harvest progression, small equipment fleet size, low-capital expenditures, and maximum labor utilization.

This study examined the effects of climate change on rice production in 30 Chinese provinces spanning 1998–2017. The study used the pooled mean group technique to capture the long-run and short-run effects of changing climatic conditions on rice production. It further employed the Dumitrescu–Hurlin panel causality test to examine the path of causality between the key variables and rice production. The study found that, in the long run, average temperature negatively influenced rice production, but average rainfall had a positive effect on rice production. The results indicated that the cultivated area and fertilizer usage were positively related to rice production in the long run. The short-run results accentuated that average temperature favourably influenced nationwide rice production, whereas average rainfall had no substantial effect on national rice production. The cultivated area had a significant positive short-term relationship with rice production, although the impact of fertilizer usage on rice production was negligible in the short run. Besides, the results established a bidirectional causality between rice output and the cultivated area, but there was a one-way causality running from fertilizer usage to rice output. Finally, the results indicated that, except for rainfall, a unidirectional causality exists between temperature and rice production. The study, therefore, recommends that in the case of crop failure due to weather conditions, policymakers could implement a new pricing policy to mitigate the deterioration of the farmers’ income. The government must also develop and implement an insurance scheme that compensates farmers for catastrophes induced by rainfall deficiency.

Linking population trends to species' traits is informative for the detection of the most important threatening factors and for assessing the effectiveness of conservation measures. Although some previous studies performed such an analysis at local to continental scales, the global-scale focus is the most relevant for conservation of the entire species. Here we evaluate information on global population trends of shorebirds, a widely distributed and ecologically diversified group, where some species connect different parts of the world by migration, while others are residents. Nowadays, shorebirds face rapid environmental changes caused by various human activities and climate change. Numerous signs of regional population declines have been recently reported in response to these threats. The aim of our study was to test whether breeding and non-breeding habitats, migratory behaviour (migrants vs. residents) and migration distance, breeding latitude, generation time and breeding range size mirror species' global population trends. We found that a majority of shorebird species have declined globally. After accounting for the influence of traits and species taxonomy, linear mixed-effects models showed that populations of migratory shorebirds decreased more than populations of residents. Besides that, declines were more frequent for species breeding at high latitudes of the Northern Hemisphere, but these patterns did not hold after excluding the non-migratory species. Our findings suggest that factors linked to migration, such as habitat loss as well as deterioration at stop-over or wintering sites and a pronounced climate change impact at high latitudes, are possible drivers of the observed worldwide population decreases.

Abstract The goal for performing heat exchanger network (HEN) retrofit is not only to reduce utility consumption but to ensure that the retrofit is economically viable. The problem of using heat transfer enhancement for retrofit lies with the uncertainty of the best location in which to apply enhancement, the augmentation level and dealing with downstream effects after enhancement is conducted. To solve these problems, a systematic methodology is proposed. The first step in this methodology is the identification of candidate heat exchangers. In the second step, two methods, sensitivity analysis and an area ratio approach are compared for the identification of the best candidate heat exchangers to enhance. Heat transfer enhancement is then performed on the best candidate heat exchanger and, a non-linear optimisation based model is used to deal with the downstream effects after enhancement, subject to meeting set constraints on the HEN, such as the stream target temperatures and heat transfer area. Following this approach, the problems posed by the use of enhancement for retrofit can be addressed in a simple and computationally inexpensive manner. Heat transfer enhancement is an attractive option for HEN retrofit as it can provide energy saving without the need for topology modifications and additional heat transfer area with an added benefit of reduced implementation time, as modifications can be carried out during normal shutdown periods.

In a climate constrained future, hybrid energy-economy model coupling gives additional insight into interregional competition, trade, industrial delocalisation and overall macroeconomic consequences of decarbonising the energy system. Decarbonising the energy system is critical in mitigating climate change. This chapter summarises modelling methodologies developed in the ETSAP community to assess economic impacts of decarbonising energy systems at a national level. The preceding chapter focuses on a global perspective. The modelling studies outlined here show that burden sharing rules and national revenue recycling schemes for carbon tax are critical for the long-term viability of economic growth and equitable engagement on combating climate change. Traditional computable general equilibrium models and energy systems models solved in isolation can misrepresent the long run carbon cost and underestimate the demand response caused by technological paradigm shifts in a decarbonised energy system. The approaches outlined within have guided the first evidence based decarbonisation legislation and continue to provide additional insights as increased sectoral disaggregation in hybrid modelling approaches is achieved.

Abstract In recent years the use of non-intrusive and non-invasive imaging techniques to safely interrogate non-nuclear (industrial) storage vessels or process units has seen a significant increase. The nature of material found within active ‘legacy waste’ storage vessels and other radiation shielded vessels coupled with the distinct lack of access makes representative sampling or visual inspection of the vessel extremely problematic and in some cases impossible. However, until recently, the radiation shielding which is commonplace on all nuclear sites has rendered existing remote non-intrusive imaging techniques useless. This is due to the limiting penetrative power of X-rays and gamma-rays as well as lack of access for other semi-invasive techniques such as electrical and acoustic imaging. Cosmic ray muon based imaging systems have great potential. This is because muons have very high energies (up to 10 12 GeV) and therefore, offer a superior penetrative power which provides a means to ‘peer through’ objects which otherwise would be inaccessible. Such objects may include lead lined silo or vessels as well as various intermediate material transport modules. Because muons only show detectable interactions with high atomic number material they also offer a means to detect the quantity and location of heavy metal elements and their associated compounds. In this work the first attempts at two-dimensional muon attenuation mapping are described. More specifically multiple plane prototype muon detection system has been used to image the resultant attenuation maps for a number of lead phantoms. This opens up possibilities for the collation of muon trajectory data which in turn can be used to track muon events both entering and leaving the object of interest allowing attenuation based image processing. It is believed that future work in this area will serve to significantly improve both the coverage area and the spatial resolution of the system though improved detector technology providing a powerful tool for the rendering of either large or dense objects.

AbstractThis chapter assesses the macroeconomic effects of carbon‐energy taxation introduced under unilateral environmental tax reform (ETR) in the 1990s undertaken in six member states of the European Union: Denmark, Finland, Germany, the Netherlands, Sweden, and the UK. The effects are estimated using the large‐scale Energy–Environment–Economy (E3) model for Europe, E3ME, which covers the countries involved as well as the complete single market, so that the effects on other economies can be considered, along with any effects on competitiveness. The method is to identify the key characteristics of the green tax reform packages and include these in the modelling of the price and non‐price effects of the ETR on energy use and international trade in E3ME. The effects are then compared with a ‘reference case’ (i.e. a counterfactual case) generated by E3ME over the period 1995–2012, including current and expected developments in the EU economy, e.g. the impact of the EU Emission Trading Scheme, but without the ETR. The revenue recycling meant that the cost of ETR to the economy was significantly reduced and in several cases resulted in an increase in GDP. The method for revenue recycling strongly affects the results, as does the scale of exemptions offered to certain fuel user groups.

The work presented herein reports on the investigation of the biogas dry reforming catalytic performance of LaNiO3 (LNO), La0.8Sm0.2NiO3 (LSNO), La0.8Pr0.2NiO3 (LPNO) and La0.8Ce0.2NiO3 (LCNO). The perovskite-type materials were synthesized via citrate sol-gel and characterized using XRD, N2 physisorption H2-TPR, H2-TPD, TEM, HAADF-STEM and XPS. The performance of all catalysts in terms of both activity and stability was examined in order to assess the effect of temperature on the CH4 and CO2 conversion, as well as on the H2 and CO yield and the H2/CO molar ratio of the produced gas mixture. Experimental results showed that modification of LaNiO3 with Sm and Pr enhanced the catalytic performance in terms of catalytic stability and reduced the order/crystallinity of the deposited coke. A theoretical model was also produced in Python with the purpose of simulating the catalytic performance. Modelling results showed a good agreement with the experimental values and therefore confirm the validity of the model for predicting the dry reforming catalytic performance.