A dwelling-level investigation into the physical and socio-economic drivers of domestic energy consumption in England

The UK Government's Department for Energy and Climate Change has been investigating the feasibility of developing a national energy efficiency data framework covering both domestic and non-domestic buildings. Working closely with the Energy Saving Trust and energy suppliers, the aim is to develop a data framework to monitor changes in energy efficiency, develop and evaluate programmes and improve information available to consumers. Key applications of the framework are to understand trends in built stock energy use, identify drivers and evaluate the success of different policies. For energy suppliers, it could identify what energy uses are growing, in which sectors and why. This would help with market segmentation and the design of products. For building professionals, it could supplement energy audits and modelling of end-use consumption with real data and support the generation of accurate and comprehensive benchmarks. This paper critically examines the results of the first phase of work to construct a national energy efficiency data-framework for the domestic sector focusing on two specific issues: (a) drivers of domestic energy consumption in terms of the physical nature of the dwellings and socio-economic characteristics of occupants and (b) the impact of energy efficiency measures on energy consumption.

Assimilation of sea-ice concentration in a global climate model — physical and statistical aspects

We investigate the initialization of Northern-hemisphere sea ice in the global climate model ECHAM5/MPI-OM by assimilating sea-ice concentration data. The analysis updates for concentration are given by Newtonian relaxation, and we discuss different ways of specifying the analysis updates for mean thickness. Because the conservation of mean ice thickness or actual ice thickness in the analysis updates leads to poor assimilation performance, we introduce a proportional dependence between concentration and mean thickness analysis updates. Assimilation with these proportional mean-thickness analysis updates significantly reduces assimilation error both in identical-twin experiments and when assimilating sea-ice observations, reducing the concentration error by a factor of four to six, and the thickness error by a factor of two. To understand the physical aspects of assimilation errors, we construct a simple prognostic model of the sea-ice thermodynamics, and analyse its response to the assimilation. We find that the strong dependence of thermodynamic ice growth on ice concentration necessitates an adjustment of mean ice thickness in the analysis update. To understand the statistical aspects of assimilation errors, we study the model background error covariance between ice concentration and ice thickness. We find that the spatial structure of covariances is best represented by the proportional mean-thickness analysis updates. Both physical and statistical evidence supports the experimental finding that proportional mean-thickness updates are superior to the other two methods considered and enable us to assimilate sea ice in a global climate model using simple Newtonian relaxation.

Assimilation of sea-ice concentration in a global climate model — physical and statistical aspects

We investigate the initialisation of Northern Hemisphere sea ice in the global climate model ECHAM5/MPI-OM by assimilating sea-ice concentration data. The analysis updates for concentration are given by Newtonian relaxation, and we discuss different ways of specifying the analysis updates for mean thickness. Because the conservation of mean ice thickness or actual ice thickness in the analysis updates leads to poor assimilation performance, we introduce a proportional dependence between concentration and mean thickness analysis updates. Assimilation with these proportional mean-thickness analysis updates leads to good assimilation performance for sea-ice concentration and thickness, both in identical-twin experiments and when assimilating sea-ice observations. The simulation of other Arctic surface fields in the coupled model is, however, not significantly improved by the assimilation. To understand the physical aspects of assimilation errors, we construct a simple prognostic model of the sea-ice thermodynamics, and analyse its response to the assimilation. We find that an adjustment of mean ice thickness in the analysis update is essential to arrive at plausible state estimates. To understand the statistical aspects of assimilation errors, we study the model background error covariance between ice concentration and ice thickness. We find that the spatial structure of covariances is best represented by the proportional mean-thickness analysis updates. Both physical and statistical evidence supports the experimental finding that assimilation with proportional mean-thickness updates outperforms the other two methods considered. The method described here is very simple to implement, and gives results that are sufficiently good to be used for initialising sea ice in a global climate model for seasonal to decadal predictions.

Auto ID-Bridging the physical and the digital on construction projects

This book looks at how auto-ID has evolved and how it can be used in the construction industry and across projects from the perspective of all the stakeholders, from owners to design consultants, contractors and the supply chain. It could help to improve efficiency, reduce costs, ensure quality, protect the environment, and enhance safety.

Replacing fat and sugar with inulin in cakes: bubble size distribution, physical and sensory properties

The replacement of fat and sugar in cakes is a challenge as they have an important effect on the structural and sensory properties. Moreover, there is the possibility to incorporate an additional value using novel replacers. In this work, inulin and oligofructose were used as fat and sugar replacers, respectively. Different combinations of replacement levels were investigated: fat replacement (0 and 50 %) and sugar replacement (0, 20, 30, 40 and 50 %). Simulated microbaking was carried out to study bubble size distribution during baking. Batter viscosity and weight loss during baking were also analysed. Cake characteristics were studied in terms of cell crumb structure, height, texture and sensory properties. Fat and sugar replacement gave place to batters with low apparent viscosity values. During heating, bubbles underwent a marked expansion in replaced cakes if compared to the control cake. The low batter stability in fat-replaced samples increased bubble movement, giving place to cakes with bigger cells and less height than the control. Sugar-replaced samples had smaller and fewer cells and lower height than the control. Moreover, sugar replacement decreased hardness and cohesiveness and in- creased springiness, which could be related with a denser crumb and an easily crumbled product. Regarding the sensory analysis, a replacement up to 50 % of fat and 30 % of sugar, separately and simultaneously, did not change remarkably the overall acceptability of the cakes. However, the sponginess and the sweetness could be improved in all the replaced cakes, according to the Just About Right scales.

Diruthenium complexes with bridging diethynyl polyaromatic ligands: synthesis, spectroelectrochemistry, and theoretical calculations

This work describes syntheses and electrochemical, spectroscopic, and bonding properties in a new series of dinuclear ruthenium(II) complexes bridged by polyaromatic (biphenyl, fluorene, phenanthrene, and pyrene) alkynyl ligands. Longitudinal expansion of the π-conjugated polyaromatic core of the bridging ligands caused a reduced potential difference between the anodic steps and reinforced their bridge-localized nature, as evidenced by UV/vis/near-IR and IR spectroelectrochemical data combined with DFT and TDDFT calculations. Importantly, the intricate multiple IR ν(CC) absorption bands for the singly oxidized states imply a thermal population of a range of conformers (rotamers) with distinct electronic character. This behavior was demonstrated with more accurate DFT calculations of selected nontruncated 1e− oxidized complexes in three different conformations. The combined experimental and theoretical data reveal that thermally populated rotamers featuring various mutual orientations of the ligated metal termini and the bridging diethynyl polyaromatic moieties have a significant impact on the electronic absorption and ν(CC) wavenumbers of the singly oxidized systems.

Thermal and visual performance of real and theoretical thermochromic glazing solutions for office buildings

Thermochromic windows are able to modulate their transmittance in both the visible and the near-infrared field as a function of their temperature. As a consequence, they allow to control the solar gains in summer, thus reducing the energy needs for space cooling. However, they may also yield a reduction in the daylight availability, which results in the energy consumption for indoor artificial lighting being increased. This paper investigates, by means of dynamic simulations, the application of thermochromic windows to an existing office building in terms of energy savings on an annual basis, while also focusing on the effects in terms of daylighting and thermal comfort. In particular, due attention is paid to daylight availability, described through illuminance maps and by the calculation of the daylight factor, which in several countries is subject thresholds. The study considers both a commercially available thermochromic pane and a series of theoretical thermochromic glazing. The expected performance is compared to static clear and reflective insulating glass units. The simulations are repeated in different climatic conditions, showing that the overall energy savings compared to clear glazing can range from around 5% for cold climates to around 20% in warm climates, while not compromising daylight availability. Moreover the role played by the transition temperature of the pane is examined, pointing out an optimal transition temperatures that is irrespective of the climatic conditions.

PHYSICAL AND CHEMICAL CHARACTERISTICS OF FROZEN GROUND BEEF AND AGED BEEF MEAT FROM BOS INDICUS STEERS SUPPLEMENTED WITH alpha-TOCOPHEROL ACETATE

The objective of this study was to evaluate the effects of diet supplementation with vitamin E on the physical and chemical characteristics of ground, frozen and stored or aged Quadriceps femoris (QF) and Longissimus dorsi (LD) muscles from Nellore steers fed high concentrate diets. Muscles were obtained from 24 animals that were 30 months old with a mean live weight of 279 kg. Half of the animals received daily doses of 1,000 mg of alpha-tocopherol acetate (VIT E) per head per day that was added to 100 g of corn meal. The other half received 100 g of corn meal without the antioxidant. Twenty-four hours after slaughtering, QF samples from each animal were ground, frozen and stored for up to 6 months. In addition, 4 samples from the LD of each animal were vacuum packed individually and kept for 21 days. All samples were analyzed to determine the pH, color and water-holding-capacity. The VIT E supplementation improved only the water loss characteristics of frozen ground QF and did not have any positive effect on the physical-chemical characteristics of the aged LD.

Evaluation of mechanical, physical and thermal performance of cement-based tiles reinforced with vegetable fibers

The objective of this work was to analyze mechanical, physical and thermal performance of roofing tiles produced with several formulations of cement-based matrices reinforced with sisal and eucalyptus fibers. The physical properties of the tiles were more influenced by the fiber content of the composite than by the type of reinforcement. The type of the fiber was the main variable for the achievement of the best results of mechanical properties. Exposure to tropical climate has caused a severe reduction in the mechanical properties of the composites. After approximately four months of age under external weathering the toughness of the vegetable fiber-cement fell to 53-68% of the initial toughness at 28 days of age. The thermal performance showed that roofing tiles reinforced with vegetable fiber are acceptable as substitutes of asbestos-cement sheets. (c) 2006 Elsevier Ltd. All rights reserved.

An experimental and theoretical investigation into positron and electron scattering from formaldehyde

We report on measurements of total cross sections (TCSs) for positron scattering from the fundamental organic molecule formaldehyde (CH(2)O). The energy range of these measurements was 0.26-50.3 eV, whereas the energy resolution was similar to 260 meV. To assist us in interpreting these data, Schwinger multichannel level calculations for positron elastic scattering from CH(2)O were also undertaken (0.5-50 eV). These calculations, incorporating an accurate model for the target polarization, are found to be in good qualitative agreement with our measured data. In addition, in order to compare the behaviour of positron and electron scattering from this species, independent atom model-screened additivity rule theoretical electron TCSs, now for energies in the range 1-10 000 eV, are also reported.

EXPERIMENTAL AND THEORETICAL STUDY OF SHYNTESIS OF N-ALKYL-NITROIMIDAZOLES.

In this work we realized and experimental and theoretical study of the N-alkylation of nitroimidazoles. The N-alkyl-2-methyl-nitroimidazoles correspond to biologically active molecules, obtained by reaction of 2-methyl-5-nitroimidazole and different alkyl halides. This reaction showed the formation of a mixture of isomeric products in different proportions, denominated like N-alkyl-2-methyl-4-nitroimidazole and N-alkyl-2-methyl-5-nitroimidazole, respectively. The reaction suggestes the formation of a tautomeric equilibrium, which generates two nucleophilic sites susceptible to electrophilic attack by the alkyl halide. The local nucleophilic reactivity of the nitroimidazole nng is determined using local reactivity indices such as the Fukui function and the electrostatic potential, besides the electronic localization function (ELF). The Fukui function was integrated for each atom using partition schemes based on analysis of Mulliken charges and natural bond orbital (NBO). Finally the reaction profiles were assessed. The results show a minor difference in the local reactivity. Nevertheless a significant difference in energy barriers is observed explaining the formation of an isomeric product over another. These results agree quite well with the experimental data.

Identification of species formed after pyridine adsorption on iron, cobalt, nickel and silver electrodes by SERS and theoretical calculations

The adsorption of pyridine (py) on Fe, Co, Ni and Ag electrodes was studied using surface-enhanced Raman scattering (SERS) to gain insight into the nature of the adsorbed species. The wavenumber values and relative intensities of the SERS bands were compared to the normal Raman spectrum of the chemically prepared transition metal complexes. Raman spectra of model clusters M(4)(py) (four metal atoms bonded to one py moiety) and M(4)(alpha-pyridil) where M = Ag, Fe, Co or Ni were calculated by density functional theory (DFT) and used to interpret the experimental SERS results. The similarity of the calculated M(4)(py) spectra with the experimental SERS spectra confirm the molecular adsorption of py on the surface of the metallic electrodes. All these results exclude the formation of adsorbed alpha-pyridil species, as suggested previously. Copyright (C) 2009 John Wiley & Sons, Ltd.

The interaction between atoms of Au and Cu with clean Si(111) surface: A study combining synchrotron radiation grazing incidence X-ray fluorescence analysis and theoretical calculations

In order to evaluate the interactions between Au/Cu atoms and clean Si(l 11) surface, we used synchrotron radiation grazing incidence X-ray fluorescence analysis and theoretical calculations. Optimized geometries and energies on different adsorption sites indicate that the binding energies at different adsorption sites are high, suggesting a strong interaction between metal atom and silicon surface. The Au atom showed higher interaction than Cu atom. The theoretical and experimental data showed good agreement. Crown Copyright (C) 2009 Published by Elsevier B.V. All rights reserved.

Experimental and theoretical investigation of compression of a cylinder using a rotating platen

A rig was constructed to carry out compression of an aluminum cylinder with a monotonically rotating platen. The tests carried out showed that the compression load decreased and the side wall bulge severity reduced when the die was rotated. Not all the work supplied by the rotating dies was transferred to the work-piece; circumferential slippage was frequently observed at the die/material interface. This slippage was quantified by comparing measurements made during interrupted testing with the angular velocity of the die. A compound velocity field based on an exponential cusp description of the barreling was employed in an upper bound analysis. An approximate analytical solution was obtained for the degree of barreling and the compression pressure. The model is able to reproduce the decrease in barreling and compression loads with increasing die rotation.