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Abstract Building-integrated photovoltaics (BIPV) is a growing reality worldwide and its development involves implementing techniques to log and estimate the solar resources available. In this paper an easy methodology for the pre-classification of facades in BIPV projects has been described. This step is previous to the calculation of the complete solar potential in a building, and don't include the shape and shading factors. The proposed methodology covers the development of a new model that allows the irradiation factor (IF) to be estimated on facades with only 2 input parameters: the latitude of the place and the azimuth angle of the photovoltaic generator. The necessary tools to assess the “Energetic Efficiency Rating” for BIPV facades are provided, as an initial stage to be applied by architects and engineers.

Use of a pilot-scale fixed-film bioreactor was investigated for remediation of bromate contamination within groundwater. Bromate reduction with stoichiometric production of bromide was observed, providing supporting evidence for complete reduction of bromate with no production of stable intermediates. Reduction of 87-90% bromate from an influent concentration of 1.1 mg L(-1) was observed with retention times of 40-80 h. Lower retention times led to decreases in bromate reduction capability, with 11.5% removal at a 10 h retention time. Nitrate reduction of 76-99% from a 30.7 mg L(-1) as NO(3)(-) influent was observed at retention times of 10-80 h, although an increase in nitrite production to 2.7 mg L(-1) occurred with a 10 h retention time. Backwashing was not required, with the large plastic packing media able to accommodate biomass accumulation without decreases in operational efficiency. This study has provided proof of concept and demonstrated the potential of biological bromate reduction by fixed-film processes for remediation of a bromate contaminated groundwater source.

Abstract This paper presents a theoretical and experimental investigation about the modelling of a 1:45 scale prototype Wave Energy Converter (WEC). An analytical model is implemented to describe its behaviour in a wave tank. The aim is to provide a contribution to modelling tools used for WEC characterisation and design. Hydrodynamic characterisation software is avoided in favour of a simpler and more versatile design tool destined to a wider range of users. Therefore, an alternative approach is presented, based on mechanical analogies and the use of Matlab/Simulink/SimMechanics environment. This analytical model was constructed using linear wave theory, coupled with a non-linear model for the device and its power take-off system (PTO). Assumptions on incident waves and geometric properties of the device were required and implemented on the basis of literature of naval architecture, ships stabilization and control issues. Simulation results were compared and validated with those obtained in the same range of experimental tests of the prototype in wave tank. Trends and values of both investigation techniques show a good agreement, indicating the validity of the methodology adopted and leaving space for future improvements of the same. Finally, as example of application, the model was applied in a show case in order to estimate the energy yield by the WEC if scaled to real size, using Froude scaling. Results are encouraging and show the viability of the proposed design.

Abstract The almost two-dimensional steady-state rates of heat loss from arrays of uniformly-spaced vertical rectangular fins, extending upwards—in otherwise stagnant air—from horizontal heated bases, have been measured. (The vertical air gaps between the fins were closed at their sides, by insulated vertical end-barriers.) The effects of various combinations of height, thickness and spacing of the fins, for different base temperatures (in the range 40 to 100°C), have been studied. For the configuration considered, in a normal ambient environment (∼ 20°C), there is an optimal fin spacing (⋍ 16 mm) corresponding to the greatest steady-state rate of free convective/conductive heat loss through the air from the finned system, and this is almost independent of the temperature of the heat exchanger base (in the range 40–100°C). At this optimal spacing for base temperatures not greater than 50°C, the convective/conductive heat transfer rate from the array increases with the fin height up to about 60 mm, so that it would be uneconomic to employ taller fins if convection/conduction is dominant compared with radiation. If the radiation contribution is also considered, then the optimal spacing corresponding to the maximum total steady-state rate of heat loss through the air is somewhat less than the optimal spacing for which, under the same temperature conditions, the maximum steady-state rate of convective/conductive heat leak occurs. The greater the emissivity of the heat exchanger surfaces, the narrower the optimal uniform gaps between the fins. A two-dimensional finite-difference computer program has been composed to predict the temperature distribution throughout the heat exchanger for a stipulated ambient environmental temperature and experimentally-determined distribution of the heat transfer coefficient over the surfaces of the exchanger. This enables, for instance, any hot spots to be located prior to a proposed design being built.

Abstract A series of Ultraviolet-B broadband solar irradiance, 280–315 nm, measured during the period 2002–2011 in Valladolid (Spain) is analysed. UV-B daily values follow the pattern of the solar elevation angle. Daily maximum value occurred in June, 50.29 kJ m −2 , and minimum, 0.88 kJ m −2 , in December. The total accumulated UV-B irradiation along a mean year reached 7.1 MJ m −2 . The elemental statistical characteristics of hourly and daily irradiation show that the inter-quartile range is small in winter and increases in spring; maximum stability in UV-B takes place at solar noon and around summer; it can be concluded that this maximum may be considered representative of the UV-B irradiance values. The monthly-integrated UV-B irradiation values show a large annual cycle with a maximum in July, when the influence of the annual ozone column diminishes and summer solstice occurs. The results show that the harmonic analysis permits constructing long-term monthly UV-B values under clear and all sky conditions and from low number of parameters. The UV-B percentage attenuated by the atmosphere increases from winter to summer, a maximum value of 8% is obtained in summer and a minimum of 2% in winter. The cloudiness effects on the surface solar UV-B radiation are strong during the winter months, being the cloud transmittance 0.7 in December and 0.94 in July.

Abstract This paper addresses the problem of how to synthesize mass and heat exchange processes, in which stream flowrates and their inlet compositions and temperatures may vary according to a set of discrete values. A unified hyperstructure representation of mass and heat exchange alternatives is introduced to account for all mass and heat integration possibilities. A multiperiod mixed integer nonlinear programming (MINLP) model is then developed, where a total annualized cost is minimized by balancing capital investment cost (of the heat and mass exchange equipment and their interconnections) to operating cost (of the hot-cold utilities, mass separating agents, etc.). As illustrated with the example problems, the proposed model can be effectively employed for the synthesis of flexible heat exchanger networks (HENs) and mass exchanger networks (MENs) separately or, for the synthesis of separation processes involving both heat and mass transfer.

Turbulent spots were generated artificially to simulate natural spots in the transitional boundary layer. The spots at the final stage under zero and adverse pressure gradients were measured using conventional hotwire anemometry technique. Ensemble averages of the velocity traces were calculated and velocity profiles through the spots and the surrounding region were plotted. The spots are represented by the ensemble average of the velocity perturbations. The integral boundary layer properties are derived and compared through the spots. The effect of the pressure gradient on the turbulent spots is analysed with the structure of the spots and the ‘calmed region’ following the spots.

Genuine Savings (GS), also known as ‘net adjusted savings’, is a composite indicator of the sustainability of economic development. Genuine Savings reflects year-on-year changes in the total wealth or capital of a country, including net investment in produced capita, investment in human capital, depletion of natural resources, and damage caused by pollution. A negative Genuine Savings rate suggests that the stock of national wealth is declining and that future utility must be less than current utility, indicating that economic development is non-sustainable (Hamilton and Clemens, 1999). We make use of data over a 150 year period to examine the relationship between Genuine Savings and a number of indicators of well-being over time, and compare the relative changes in human, produced, and components of natural capital over the period. Overall, we find that the magnitude of genuine savings is positively related to changes in future consumption, with some evidence of a cointegrating relationship. However, the relationships between genuine savings and infant mortality or average heights are less clear.

Abstract In this study, the chemical interesterification of oil with methyl acetate using potassium hydroxide, methoxide and polyethylene glycolate as catalysts was investigated. The reactions were performed at 50 °C using the range methyl acetate 12 mol mol −1 of refined sunflower oil to a value of 100 mol mol −1 and the range of potassium methanolate to oil was 100–500 mmol mol −1 . The effect of methanol and water on the catalyst and reagents was to reduce the yield of triacetin, forming diacetin, monoacetin and glycerol instead. A compromise between the product yield, reaction kinetics and methyl acetate recovery was achieved with the conditions methyl acetate to oil 50 mol mol −1 and catalyst to oil 100 mmol mol −1 when potassium methoxide was used as a catalyst and the reagents were dehydrated. Under these conditions, equilibrium was reached within the first 15 min of the reaction. The mass fractions of fatty acid methyl esters (FAME) and triacetin in the product were 76.7% and 17.2%, respectively, with a mass fraction of 4.7% for the intermediate diacetinmonoglyceride. Diacetin, monoacetin and glycerol were also found at a mass fraction of 1.2%.

Ethanol is the most common human teratogen, and its consumption during pregnancy can produce a wide range of abnormalities in infants known as fetal alcohol spectrum disorder (FASD). The major characteristics of FASD can be divided into: (i) growth retardation, (ii) craniofacial abnormalities, and (iii) central nervous system (CNS) dysfunction. FASD is the most common cause of nongenetic mental retardation in Western countries. Although the underlying molecular mechanisms of ethanol neurotoxicity are not completely determined, the induction of oxidative stress is believed to be one central process linked to the development of the disease. Currently, there is no known effective strategy for prevention (other than alcohol avoidance) or treatment. In the present review we will provide the state of art in the evidence for the use of antioxidants as a potential therapeutic strategy for the treatment using whole‐embryo and culture cells models of FASD. We conclude that the imbalance of the intracellular redox state contributes to the pathogenesis observed in FASD models, and we suggest that antioxidant therapy can be considered a new efficient strategy to mitigate the effects of prenatal ethanol exposure. Birth Defects Research (Part A) 103:163–177, 2015. © 2014 Wiley Periodicals, Inc.