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Measurements of absorption coefficients (σ ap , λ) and carbonaceous components (OC, EC, WSOC and levoglucosan) in PM 1 were conducted at an urban background site in southeastern Spain throughout 2021. The main goal of this research was to determine the contribution from different sources to WSOC light absorption (σ WSOC). For this, σ BrC , λ values were previously obtained. The mean contribution of BrC to total aerosol absorption was ∼29% at 370 nm, revealing a significant influence of BrC to light absorption in the study area. Assuming that BrC light absorption was from WSOC and WIOC, a multilinear regression (MLR) model was used to estimate σ WSOC and σ WIOC. Average values (mean ± SD) were very similar for both components: σ WSOC,370 = 1.6 (±0.7) Mm−1 and σ WIOC,370 = 1.9 (±0.7) Mm−1. Finally, the PMF technique coupled with MLR analysis was used to identify the sources of WSOC light absorption and estimate their contribution. Our findings point to biomass burning as the dominant source of σ WSOC during the cold season, with a contribution of ∼37%. The Mineral Dust and Secondary Nitrate sources, that were not included in the model due to their low contribution to WSOC mass concentrations, accounted for a significant percentage of σ WSOC during this period. Secondary organic aerosol was the major source during the warm season (∼56%), followed by traffic emissions (∼30%). • Sources of WSOC absorption was analysed at an urban background site in the southeast of the Iberian Peninsula. • BrC accounted for 29% of the total aerosol absorption at 370 nm, with similar contributions from WSOC and WIOC. • Marked seasonal variation of WSOC absorption, with higher levels during the cold season when BB emissions are highest. [ABSTRACT FROM AUTHOR]

This paper proposes the first application of a split-range control technique on a concentrating solar collector to improve an absorption plant production. Solar absorption plants have solar power availability in phase with cooling demand under design conditions. Thus, it is a powerful cooling technology in the context of renewable energy and energy efficiency. These plants need control systems to cope with solar irradiance intermittency, reject irradiation disturbances, manage fossil fuels backup systems and dump closed-loop thermal-hydraulic oscillations. In this work, control techniques are proposed and simulated in an absorption plant in Spain. The plant consists of a concentrating Fresnel solar collector connected to an absorption chiller. The objectives are to operate with 100% renewable solar energy and avoid safety defocus events while reducing temperature oscillations and control actuators effort. Firstly, the current available plant controllers are defined, then two modifications are proposed. The first modification is a split-range controller capable of manipulating both flow and defocus of the Fresnel collector, the second modification is a PI controller to substitute the original chiller on-off controller. The results compare, through validated models, the different control systems and indicate that using both proposed controllers reduces 94% of the sum of actuators effort and 43% of the integral of absolute set-point tracking error compared to the plant's factory pre-set controllers. The suggested controllers increase 66% of energy production and 63% of exergy production. Besides, the split-range technique can be extended to any concentrating solar collector control. [Display omitted] [ABSTRACT FROM AUTHOR]

High‐resolution spectroscopy of strong chromospheric absorption lines delivers nowadays several millions of spectra per observing day, when using fast scanning devices to cover large regions on the solar surface. Therefore, fast and robust inversion schemes are needed to explore the large data volume. Cloud model (CM) inversions of the chromospheric Hα line are commonly employed to investigate various solar features including filaments, prominences, surges, jets, mottles, and (macro‐) spicules. The choice of the CM was governed by its intuitive description of complex chromospheric structures as clouds suspended above the solar surface by magnetic fields. This study is based on observations of active region NOAA 11126 in Hα, which were obtained November 18–23, 2010 with the echelle spectrograph of the vacuum tower telescope at the Observatorio del Teide, Spain. Principal component analysis reduces the dimensionality of spectra and conditions noise‐stripped spectra for CM inversions. Modeled Hα intensity and contrast profiles as well as CM parameters are collected in a database, which facilitates efficient processing of the observed spectra. Physical maps are computed representing the line‐core and continuum intensity, absolute contrast, equivalent width, and Doppler velocities, among others. Noise‐free spectra expedite the analysis of bisectors. The data processing is evaluated in the context of "big data," in particular with respect to automatic classification of spectra. [ABSTRACT FROM AUTHOR]

The aim of this work was to address whether the growing location of tomato could generate a different (poly)phenol profile able to affect both in vivo absorption and (poly)phenol metabolite pattern upon tomato consumption. uHPLC-MS n analyses allowed to obtain a detailed (poly)phenol profile of tomatoes from two locations in Spain, quantifying 57 (poly)phenolic compounds. However, local and non-local tomatoes showed a different concentration of their native (poly)phenols, which could be attributed to diverse cultivation origin. Rat serum was analysed after an acute tomato feeding. Seven phenolic metabolites were quantified through uHPLC-MS n. Pharmacokinetic parameters were further evaluated, revealing different serum concentrations of (poly)phenolic metabolites between tomatoes. The maximum peak serum concentrations, reached mainly after 2 h after ingestion, led to suppose that serum metabolites were mostly derived from absorption in the upper gastrointestinal tract. The growing location of tomatoes affected both the content of native (poly)phenols and their in vivo absorption. [ABSTRACT FROM AUTHOR]

Spanish paprika was clustered on the basis of the Spanish Protected Designation of Origin “Pimentón de La Vera” by molecular absorbance and fluorescence with principal component analysis and parallel factor analysis. Rapid extraction of carotenoids, capsaicinoids, and tocopherols was optimized; the best conditions included ethanol as the extractant, an extraction time of 10 min in an ultrasonic bath, and a sample size of 0.1 g. The procedure provided good precision with a relative standard deviation of 1.2% for four samples. Molecular absorption spectra were obtained from 250 to 600 nm and fluorescence excitation and emission spectra were collected from 200 to 295 nm and 300 to 400 nm, respectively. Forty-eight “Pimentón de La Vera” paprika samples and 19 samples from other origins were characterized. A principal component analysis model was constructed from the absorption spectra and clustering was obtained based on the origin. Parallel factor analysis was performed on the fluorescence data and better characterization of the origin was obtained. [ABSTRACT FROM PUBLISHER]

Abstract: Despite its attractiveness, solar cooling technology is still in an early stage of development. Most installations currently in operation show differences in the collector area per kilowatt of cooling capacity that cannot be explained only by project-specific circumstances. The purpose of this paper was twofold. First, to answer some questions that came up during the design process of the plant by using a TRNSYS system model and statistical tools. Second, to gain knowledge about the plant operation and validate the TRNSYS model through measured data. The system was equipped with a flat-plate collector field of 38.4m2. A lithium bromide-water single-effect absorption chiller (17.6kW) was selected in order to provide chilled water to fan-coils. Performance data were registered at the solar plant working with a 1000-l heat storage tank and a required temperature of 80°C to drive the absorption machine. An average of 29% of the solar energy incident on the solar collectors’ surface was transferred to the hot water storage. The registered average COP of the absorption chiller was 0.691. The performance data were compared with the values predicted by the TRNSYS plant model and a high level of agreement was obtained. [Copyright &y& Elsevier]

Abstract: The main problem with the agricultural use of sewage sludge is the higher heavy metal (mainly zinc) concentrations in the sludge than in the soil. In Spain, R.D. 1310/1990 and European Directive 86/278 limit the total heavy metal concentration in soil but not the changes in heavy metal availability, which directly affect plant absorption and thereby represent a possible risk to human health. The heavy metal availability in soil depends on different factors (pH, soil organic matter, and weather) and the type of soil (agriculture or forest). This study evaluate the effects of two types of soils (forest and agriculture), two types of vegetation (natural and sown), and two types of fertilisation (sludge fertilisation and mineral fertilisation, with a no fertiliser control) in afforested and treeless pastures and in sown and unsown forestlands of Northwest Spain on the total and available Zn concentration in soil and the concentration of Zn in grasslands. The experimental design was completely randomised with nine treatments and three replicates. The fertilisation with sewage sludge increased the total, Mehlich 3 and sward Zn concentrations in forest and agriculture soils, and the levels of Zn were lower in the forest than in the agriculture soils probably because of the low soil pH in the former which probably limited the mineralisation of the sludge in the forest soil. Therefore, there is still a potential source of Zn in forest soils than in agriculture soils, when the incorporation conditions improve. This makes advisable to extend the period without grazing after sewage sludge inputs in forest than agriculture soils to avoid direct Zn intake by animals through the soil consumption. The effect of the application of sewage sludge on sward Zn concentrations was more relevant in unsown pastures of forest soils than in agriculture soils due to the different absorption capacity of unsown compared with sown species. Zinc inputs from sewage sludge to soils did not cause harmful effects on plants or animals. However, the management of heavy metal availability must be included by policy makers in further directives to better evaluate environmental risk. Moreover, Zn maintenance requirements of animals like goats, horses, bovines and ovine were not often reached, which may make advisable to provide Zn supplement to animals if their nourishment is derived solely from these pastures. [Copyright &y& Elsevier]

Abstract: Continuous measurements of black carbon (BC) concentrations performed at Granada, an urban location in southeast Spain, using a Multi-Angle Absorption Photometer from December 2005 to November 2008, are analysed and discussed here. The daily mean BC concentrations showed considerable day-to-day variations and were found to vary from low values of 0.5 μg m−3 to high values of 8.6 μg m−3, with overall mean and standard deviation of 3.0 ± 1.5 μg m−3. The annual mean BC concentrations were similar during 2006 and 2007 (3.2 ± 1.4 μg m−3 and 3.1 ± 1.6 μg m−3, respectively), but decreased by about 16–18% to 2.6 ± 1.4 μg m−3 in 2008. This reduction is not only observed in the mean value, but also in the median, third and first quartiles. A Mann–Whitney test at 0.05 significance level confirms that the BC concentration difference between 2006 and 2007 is statistically no significant while the BC concentration in 2008 tends to be less than that in 2006–2007. Analysis of meteorological conditions suggested that although the day-to-day variations in BC concentrations were driven mostly by meteorology, the reduction in the use of fossil fuels due to economic slowdown contributed significantly to the observed decrease in BC concentrations in 2008. Under conditions dominated by local source emissions, the effect of the economic crisis on BC concentration was more pronounced. For the three analysed years, BC concentrations obtained during winter were higher than those measured during summer, probably due to increased emissions from domestic heating and less intense vertical mixing in winter season, which lead to the confinement of the BC particles near the surface. The monthly mean BC concentrations were lower in 2008 than in 2006–2007 for almost every month of the year. In all years BC concentrations exhibited a clear diurnal pattern, with two maxima and two minima within a day. There were no differences among the daily patterns for 2006, 2007 and 2008 except for a general reduction in BC concentrations on 2008, especially during morning and evening traffic hours. For every day of the week, BC concentrations were lower on 2008 than in 2006 and 2007 and this reduction was more pronounced on working days, when BC concentrations were high. [Copyright &y& Elsevier]

Abstract: An experimental solar energy facility was designed to meet as much of the heating demand in a typical Spanish dwelling as possible. With a view to using the facility during the summer and preventing overheating-induced deterioration of the solar collectors in that season of the year, an absorption chiller was fitted to the system to produce solar-powered air conditioning. The facility operated in solar space heating mode in the winter of 2008–2009 and in cooling mode during the summer of 2008. The design was based on a new type of flat plate vacuum solar collectors that delivered higher efficiency than conventional panels. This type of collectors can reach temperatures of up to 110°C in the summer and up to 70°C on the coldest winter days. The solar facility comprised a 48-m2 (with a net area of 42m2) solar collector field, a 25-kW plate heat exchanger, a 1500-l storage tank, a 4.5-kW (Rotartica) air-cooled absorption chiller and several fan coils. The facility was tested by using it to heat and cool an 80-m2 laboratory located in Madrid. As the average area of Spanish homes is 80m2, the findings were generally applicable to national housing. The solar facility was observed to be able to meet 65.3% of the space heating demand. For air conditioning, the system covered 46% of the demand, but with high indoor temperatures. In other words, the collector field was found to be able to air condition only half of the home (40m2). Lastly, the savings in CO2 emissions afforded by the use of this facility compared to conventional air conditioning were calculated, along with its amortisation period. These results have been extrapolated calculating the potential energy savings and emissions reduction for all the Spanish households. [Copyright &y& Elsevier]

Abstract: Due to the increasing energy consumption of air conditioning in buildings and the need to decrease the fossil CO2 emissions to the environment, the interest of using renewable energy sources shows up stronger than ever. We present a general study whose aim is to propose a method to evaluate an upper bound in the potential of solar cooling by using some simplified models. As an example it has been applied to the very diverse climates of Spain. In the paper it has been assumed a direct solar coupling between the solar collector field and a single effect absorption cooling machine, without any intermediate solar storage tank. An equation is obtained that shows the dependence of the generator/solar-collectors equilibrium temperature on basic design parameters of the system (absorption machine-solar collectors). The paper analyzes the effect of these on the total amount of cooling produced along a typical mean year and the peak cooling power. The paper also includes a discussion on how to estimate the values and what is their physical meaning of the parameters which define the behavior of real absorption machines. Finally tables are included for the 12climates of Spain that can be used as an example of how to make a quick pre-sizing of such direct coupled system. The classification of the Spanish climates is based on general data (average monthly total horizontal solar radiation, average monthly dry temperature, etc.) and the results could be generalized for climates with the same severity. Moreover if hourly weather data is available for any place (like tmy2, bin, epw, etc. files), the procedure can be applied without further changes. [Copyright &y& Elsevier]

Marmajuelo and Malvasía are two white grape varieties grown in Spain (Canary Islands), the former only in the Canary Islands, while the latter is a variety widely spread throughout the world. At the present time, the oenological potential of these varieties grown in the Canaries has not yet been studied. Aroma precursors in musts and skins, and free volatiles in wines were determined in samples of both varieties. Aroma precursors of must and skins were isolated by absorption on XAD-2 resin, and the aglycone liberated by means of acid hydrolysis. Free volatiles from wines and from aroma precursors were extracted with dichloromethane and then analysed by GC-MS. The analysis of glycosidic aroma precursors showed that Malvasía variety presented higher contents of terpenes in grapes than those of Marmajuelo variety. In addition, some precursors of benzenic compounds presented higher contents in the musts of Malvasía with respect to those in the musts of Marmajuelo. The main difference in wine volatile composition was that cis-3-hexen-1-ol, ethyl acetate and γ-nonalactone compounds showed a significantly higher mean content in Malvasía wines than in Marmajuelo wines. Among the aroma precursors analysed, only α-terpineol, linalool oxides, 4-allyl-2,6-dimethoxyphenol, 2-methoxy-4-vinylphenol, 4-hydroxybenzaldehyde, vanillin and benzyl alcohol showed contents in grapes comparable to the levels observed in wine volatile compounds. [ABSTRACT FROM AUTHOR]

Abstract: This paper focuses on the validation of a dynamic simulation model used to describe the performance of an existing solar cooling installation located in Zaragoza (Spain). The dynamic model has been developed under the simulation environment TRNSYS. The aim of this simulation model is to dispose of a tool in order to use it to evaluate different energy improvement actions in a real solar cooling installation. This solar cooling installation has been monitored and analyzed since 2007. The COP of this experimental solar cooling system presents a great influence from its heat rejection sink, a dry cooling tower. Once the model was validated with the experimental data obtained from the real installation, it was used to predict the chiller performance with a new geothermal sink, which started to operate in 2009. The present work describes the design and validation model process, as well as the comparison between the model results and the monitoring ones with the geothermal heat rejection system. [Copyright &y& Elsevier]

Abstract: This paper presents the analysis of the performance of a solar cooling facility along one summer season using a commercial single-effect water–lithium bromide absorption chiller aiming at domestic applications. The facility works only with solar energy using flat plate collectors and it is located at Universidad Carlos III de Madrid, Spain. The statistical analysis performed with the gathered data shows the influence of five daily operational variables on the system performance. These variables are solar energy received along the day (H) and the average values, along the operating period of the solar cooling facility (from sunrise to the end of the cold-water production), of the ambient temperature (), the wind velocity magnitude (V), the wind direction (θ) and the relative humidity (RH). First order correlation functions are given. The analysis of the data allows concluding that the most influential variables on the daily cooling energy produced and the daily averaged solar COP are H, V and θ. The period length of cold-water production is determined mainly by H and . [ABSTRACT FROM AUTHOR]

Abstract: It has been studied the changes in the water repellence and colour of two commercial lime-based mortars when treated with four commercial water repellents, in the context of their possible use in the restoration work on the Tower of Gold (“Torre del Oro”) at Seville. The low pressure water absorption test revealed that the treated surfaces were regarded to be sufficiently water repellent with the exception of Tegosivin HL 100-treated Cumen mortar. This treatment was the one that induced in both mortars a significant change in colour: a shift to higher b * values (more yellow) and a decrease in lightness. [Copyright &y& Elsevier]

Abstract: A solar/gas cooling plant at the Engineering School of Seville (Spain) was tested during the period 2008–2009. The system is composed of a double-effect LiBr+water absorption chiller of 174kW nominal cooling capacity, powered by: (1) a pressurized hot water flow delivered by mean of a 352m2 solar field of a linear concentrating Fresnel collector and (2) a direct-fired natural gas burner. The objective of the project is to indentify design improvements for future plants and to serve as a guideline. We focused our attention on the solar collector size and dirtiness, climatology, piping heat losses, operation control and coupling between solar collector and chiller. The daily average Fresnel collector efficiency was 0.35 with a maximum of 0.4. The absorption chiller operated with a daily average coefficient of performance of 1.1–1.25, where the solar energy represented the 75% of generator’s total heat input, and the solar cooling ratio (quotient between useful cooling and insolation incident on the solar field) was 0.44. [Copyright &y& Elsevier]

Abstract: The time course of colored dissolved organic matter (CDOM) absorption and fluorescence were monitored during 50 to 70days of laboratory incubations with water collected in the coastal upwelling system of the Ría de Vigo (NW Iberian Peninsula) under contrasting hydrographic conditions. CDOM fluorescence at peak-T (Ex/Em, 280/350nm), characteristic of protein-like materials, decayed at a 1st order degradation rate constant (k T) of 0.28±0.13day−1 (average±SD). k T covaried (R 2 =0.86, p <0.0002) with the degradation rate of the bulk DOC (k DOC), but the protein-like materials degraded 72±23% faster than DOC. Therefore, this study confirms that the CDOM fluorescence at peak-T can be used as a proxy to a DOM fraction significantly more labile than the bulk bioavailable DOC. In parallel with the decay of DOC and protein-like fluorescence, an increase in CDOM fluorescence at peak-M (Ex/Em, 320/410nm) during the course of the incubations verified the production of marine humic-like substances as a by-product of the microbial metabolism. CDOM fluorescence at peak-M built-up at a production rate (k M) of 0.06±0.01day−1 (average±SD) in the Ría de Vigo. Furthermore, the slope of the linear regression between k DOC and k M (R 2 =0.64, p <0.001) revealed that the formation of marine humic-like substances occurred at about one fifth of the rate of net DOC consumption. [Copyright &y& Elsevier]

AbstractThe hygroscopicity and thermodynamic properties of juvenile Pinus sylvestrisL. wood taken from the submerged piles of a bridge built in 1903 over the Jiloca River, in Spain, were compared with the corresponding values of juvenile wood of the same species from recently cut trees. The 35°C and 50°C isotherms were plotted and subsequently fitted using the Guggenheim-Anderson-Boer-Dent method, and the isosteric heat of sorption was obtained through the integration method of the Clausius-Clapeyron equation. The isotherms were compared by means of the hysteresis coefficients. Infrared spectra were recorded to study the chemical modifications, and the crystal structure of the cellulose was studied by X-ray diffractograms. The submersion in water resulted in hemicellulose degradation and a decrease in the crystallinity index and the crystallite length, accompanied by a corresponding increase in the proportion of amorphous zones. Owing to this, the equilibrium moisture contents of the water logged wood are higher than in the recent wood, both in adsorption and in desorption. In terms of the thermodynamic properties, the bond energy is higher in the recent wood than in the water logged wood. [ABSTRACT FROM AUTHOR]

The copper content of 225 food, 49 beverage and twelve potable water samples were determined using atomic absorption spectrometry (AAS). Analyses of NIST and BCR reference materials demonstrated the accuracy of this technique. The highest copper levels were found in dried fruit and legumes, followed by organ meats, molluscs and crustaceans, cephalopods, cereals and sausages, respectively. In cereals, legumes and fruit, copper levels increased significantly with increasing levels of protein and decreasing carbohydrate content (p < 0.001). In meat and meat by-products, copper concentrations found in organ meats were significantly higher (p < 0.01). In fresh fish products, copper levels in shellfish were significantly higher than those measured in fish (p < 0.001). In vegetables, the copper concentrations found in mushrooms were significantly higher (p < 0.005). Mean copper concentrations analysed in cheese were statistically higher than those determined in other dairy products (p < 0.01). In beverages, copper levels determined in rum and juices were significantly higher (p < 0.001). Beverages for which a vegetable component was directly used in their manufacturing process (juices, wines and beers) had statistically higher copper levels when compared with fresh drinks. The daily dietary intake (DDI) of copper in the Andalusian diet was 1979 μg day-1 per person. Cereals, meat, meat by-products and vegetables are the food categories that are the main source of copper in the daily diet. Taking into account the dietary reference intakes and upper levels (900 and 10, 000 μg Cu day-1 for healthy adults, respectively), the mean copper DDI found indicate that for most of healthy adult individuals from the area, no adverse effects occur in relation to copper nutrition (deficiency or toxicity). Potable waters supplied 53 μg day-1, which constitutes on average 0.025% of the maximum tolerable daily intake of this element set by the Joint FAO/WHO Expert Committee. [ABSTRACT FROM AUTHOR]

Seasonal variation in size-dependence of seawater clearance rate, absorption efficiency, oxygen consumption, gill area, length of the crystalline style and dry weight of digestive gland was analyzed in cockles Cerastoderma edule from the Mundaka Estuary, Spain. Experimental determinations were performed monthly (from July 1998 to November 1999) in cockles being fed with Tetraselmis suecica (organic content: 87.84 ± 1.95%) at a concentration of 3 mm3/l for 3 days. Analysis of covariance reveals no seasonal differences in both size-dependence of seawater clearance rate and oxygen consumption, which were found to scale to dry body weight with mass-exponents of 0.56 and 0.62, respectively. No significant correlation was found between absorption efficiency and body weight. Mass-exponents for gill area, dry weight of the digestive gland and length of the crystalline style remained constant among seasons showing values of 0.62, 0.34 and 0.82, respectively. Seasonal trends for every physiological determination were calculated for a standard size (200 mg) cockle: standardized clearance rates and oxygen consumptions followed a similar trend with minimum values in winter (≈0.5 l/h and ≈100 μl O2/h, respectively) and maximum values during spring–summer (≈1.7 l/h and ≈250 μl O2/h, respectively), whereas absorption efficiency and food throughput time showed both the opposite pattern with highest values corresponding to winter months (≈50–60% and ≈5–6 h, respectively), and lowest (≈30% and ≈3–4 h, respectively) to summer–autumn. Scope for growth exhibited minimum values in winter followed by a rapid increase along the winter–spring transition, maximum values being attained in spring (May) and summer (July). Exponential decline of seasonal values of absorption efficiency associated to rising ingestion rates of organic matter presented an asymptotic minimum at 0.35. Absorption efficiency was positively related to food throughput time, whereas the latter fell to a minimum of 3.548 h with increasing food intake. So, maintenance of throughput time—and consequently absorption efficiency—along with enhanced filtering activity provided cockles with higher absorption rates improving scopes for growth registers during spring and summer. These dynamics might be explained as the consequence of the seasonal digestive adjustments in cockles, which, in fact, were found to increase the size of the digestive organs during that period. [ABSTRACT FROM AUTHOR]

Abstract: In this work, two-photon absorption fluorescence is used as a non-destructive method to detect the presence of paint upon an archaeological sample. The objective was to recover writing that, due to the discoloration caused by the passage of the time, was barely readable. The technique has been successfully applied to determine the consular date painted upon the neck of a Dressel 1A amphora found in the Roman village of Iesso (Guissona), in Catalonia. The identification of the consular date provides a terminus post quem for the foundation date for the city as well as a starting date for the Roman colonization of Hispania Citerior. [Copyright &y& Elsevier]

The sorption and desorption of six heavy metals by and from the surface or immediately subsurface horizons of eleven acid soils of Galicia (N.W. Spain) were characterized by means of batch experiments in which the initial sorption solution contained identical mass concentrations of each metal. Concentration-dependent coefficients K d were calculated for the distribution of the metals between the soil and solution phases, and the values obtained for initial sorption solution concentrations of 100mgL−1 of each metal (K d100) were used, for each soil, to order the metals as regards their sorption and retention. Pb and Cu were sorbed and retained to a greater extent than Cd, Ni or Zn, which had low K d100 values. Pb was sorbed more than any other metal. Cr was generally sorbed only slightly more than Cd, Ni or Zn, but was strongly retained, with K d100 (retention) values greater than those of Pb and Cu in soils with very low CEC (<3cmol(+) kg−1). The sorption of Pb and Cu correlated with organic matter content, while the retention of these and the other metals considered appeared to depend on clay minerals, especially kaolinite, gibbsite, and vermiculite. [Copyright &y& Elsevier]

Formation and occurrence of trihalomethanes (, , , and ) are investigated in water chlorination disinfection processes in the Barcelona''s water works plant (WWP). Twenty-three WWP variables were measured and investigated for correlation with trihalomethane formation. Multivariate statistical methods including principal component analysis (PCA), multilinear regression (MLR), stepwise MLR (SWR), principal component regression (PCR) and partial least squares regression (PLSR) have been used and compared to model and predict the complex behavior observed for the measured trihalomethane concentrations. The results, obtained by PCA as well as the evaluation of the statistical significance of the coefficients in the linear regression vectors, revealed that the most important WWP variables for trihalomethane formation were: water temperature, total organic carbon, added chlorine concentrations, UV absorbance and turbidity at different sites of the WWP, as well as other variables like wells supply flow levels and carbon filters age. Overall, MLR and PLSR methods performed the best and gave similar good predictive properties. Best results were obtained for the total sum of trihalomethane concentrations, TTHM, with average modeling and prediction relative errors of 12% and 16%, respectively. Among the individual trihalomethanes, the concentrations of were the worst predicted ones with average modeling and prediction relative errors between 21–25% and 29–31%, respectively, followed by with 23–26% and 25–27%. Better predictions were obtained for the concentrations of with relative modeling and prediction errors varying between 14–17% and 21%, and for the concentrations of with 21–24% and 23–25% errors, respectively. [Copyright &y& Elsevier]

This study showed that seasonal imagery acquired at specific stages of phenology can be used to improve the mapping accuracy of invasive willow at a catchment scale. SPOT5 XI (10 m) satellite imagery was acquired for early autumn and winter to represent the phenological stages of leaf cover and leaf fall respectively. Four classification regimes were evaluated using single- and bi-seasonal composite imagery to determine the most accurate method. Significant spectral noise was found in willow populations, especially in the winter image, due to the effects of undergrowth exposure, shadowing, topography and boundary-mixed pixels. Two noise reduction techniques were applied to the bi-seasonal composite image to improve the classification results. The noise-reduced bi-seasonal composite image was classified using the spectral angle mapper (SAM) algorithm before importation into a geographical information system. Aerial photography was used to reduce the errors of commission associated with misclassification of pastures. The class accuracy achieved for willow using the method described in this study was 77.5% (Kappa =0.87). The high cost of eradicating willow means that managers must establish priorities for control; this technique can provide a powerful tool for prioritizing control programmes and for monitoring results at a catchment scale. [ABSTRACT FROM AUTHOR]

Abstract: Background:: Enemas are used by individuals with constipation and are often required before certain medical diagnostic procedures and surgical interventions. However, abnormalities in serum electrolyte concentrations have been associated with enema use. Objective:: The aim of this study was to determine the changes in serum electrolyte concentrations (phosphorus, calcium, sodium, and potassium) and urinary phosphorus elimination after the administration of a sodium phosphate enema. Methods:: Healthy volunteers aged 35 to 70 years were eligible for this open-label, randomized, controlled, 2-period, crossover clinical trial at the Clinical Research Unit of the University Hospital of Navarra, Pamplona, Spain. The study comprised 2 one-day periods separated by a 7-day washout. All subjects were randomly assigned in a 1:1 ratio to 1 of 2 study sequences: (1) a single dose of Enema Casen® 250 mL in the first period followed by no treatment (control) in the second period, or (2) no treatment in the first period followed by a single dose of the study drug in the second period. The sequence of treatment was assigned using a randomization table that was prepared before the beginning of the study. Serum concentrations of phosphorus, sodium, potassium, and calcium were measured in both periods. Urinary phosphorus elimination was measured for 12 hours after enema administration (Ae0–12) in a subset of the subjects in the second period. Adverse events (AEs) were monitored by the investigators throughout the study. Normal ranges for the electrolytes were as follows: phosphorus, 2.5 to 5 mg/dL; calcium, 8.5 to 10.5 mg/dL; sodium, 135 to 145 mEq/L; and potassium, 3.5 to 5 mEq/L. Results:: Twenty-four subjects (12 men, 12 women; mean [SD] age, 47.8 [9.6] years [range, 36–68 years]) participated in the study. All of the subjects were white and none were smokers. Twelve hours after enema administration, mean serum phosphorus and sodium concentrations increased by a mean of 1.18 mg/dL and 1.32 mEq/L, respectively (both, P < 0.001). Mean serum phosphorus concentrations were above the upper limit of normal (5 mg/dL) at 30 and 60 minutes after enema administration. In all subjects the values returned to normal within 4 hours after enema administration; a meal was provided after a 3-hour fast. Four subjects (16.7%) had ≥1 serum phosphorus concentration measurement ≥7 mg/dL, a value that is considered serious hyperphosphatemia. A statistically significant correlation was found between phosphorus Cmax and enema retention time (r 2 = 0.452; P < 0.001). No abnormal serum concentrations were obtained for the other electrolytes measured. Phosphorus Ae0–12 was increased after enema administration by 86% (P < 0.001). No serious AEs were observed, although 13 AEs were reported in 9 subjects. None of the changes in serum electrolyte concentrations were associated with clinical symptoms. Conclusions:: Administration of an enema containing 250 mL of sodium phosphate was associated with serum phosphorus concentrations of ≥7 mg/dL in 16.7% of the healthy subjects who participated in the study; however, none of those subjects experienced hypocalcemia. Enema retention time was significantly correlated with the degree of phosphatemia. [Copyright &y& Elsevier]

Abstract: In spite of the fact that Spain is one of the EU countries with the highest solar resource on annual basis, the huge seasonal variation in solar radiation availability and the relatively short period with heating demand, make it difficult to reach significant contributions of solar energy to the buildings heating energy demand. This compromises the economic viability of big solar collector areas per capita, and introduces technical difficulties for the dissipation of the excess solar energy available in the summer months. On the other hand, in a large part of the Spanish territory, in other to reach adequate comfort conditions in our buildings, the energy demand for cooling is more important or of the same order than the heating demand. Cooling energy demand is now experiencing a fast growing rate as this comfort requirement becomes internalized. Domestic air conditioning equipments based on vapour compression cycles are being used to reach comfort conditions in some of the rooms of buildings that were designed without taking into account cooling requirements. In spite of their so far small contribution to the total building sector energy demand, these equipments are already imposing important constraints on the environment and the electricity distribution system. Solar absorption cooling arises as an interesting alternative, which at the same time allows reaching a higher solar contribution to the heating demand. However, solar cooling installations present several peculiarities with respect to the more known DHW or even heating installations, which require to incorporate a more detailed approach and additional considerations in the design and performance evaluation processes. Besides, some limitations still persist in solar absorption systems, which could make them loose their market potential for the benefit of other solar cooling options. In this paper, we present some conclusions arising from the experience gained in detailed TRNSYS dynamical simulation of some of the first commercial solar heating and cooling installations recently implemented in Spain, and analyse their perspectives in comparison with other solar cooling options. [Copyright &y& Elsevier]

Metallurgic calcines with very high mercury and methylmercury content from the Almadén mining district were analyzed by synchrotron-based microprobe techniques. Information about mercury speciation was obtained by u-EXAFS (microscopic extended X-ray absorption fine structure) spectroscopy, whereas elemental associations were evaluated by μ-XRF (microscopic X-ray fluorescence analysis) mapping. Complementary characterization methodologies, including X-ray diffraction (XRD), inductively coupled plasma-optical spectroscopy (ICP-OES), as well as a sequential extraction scheme (SES), were used to predict the potential availability of mercury. Analysis of total metal content revealed extremely high concentrations of mercury and iron (between 7 and 35 and 65-70 g kg-1, respectively) and high zinc concentrations (2.2-2.5 g kg-1, whereas other metals such as copper, nickel, and lead were found at low concentration levels (30-300 mg kg-1).μ-EXAFS results indicate that cinnabar (HgSred) is one of the main species within the studied mercury-rich particles (5-89% of total mercury content), together with more soluble mercury compounds such as Hg3(SO4)O2 (schuetteite) and HgO (5-55% of total mercury content). Additionally, element-specific μ-XRF maps of selected mercury-rich particles in the studied samples revealed an evident correlation among Hg-Pb-Ni (and S), indicating a possible geochemical linkage of these elements. Correlations were also found among Fe-Mn and Hg, which have been attributed to sorption of mercury onto oxyhydroxides of Fe and Mn. This finding was supported by results from a sequential extraction scheme, where a significant [ABSTRACT FROM AUTHOR]

Gypsum amendments in marsh soils may affect the recovery of applied P fertilizer as the addition of Ca and sulphate alters the P sorption and release capacities of soils through their effects on P adsorption and precipitation processes. The effect of gypsum on P recovery was studied in a laboratory experiment where gypsum was added at 0, 6, 20, and 100g kg[sup -1] to six representative marsh soils from SW Spain fertilized with 200 or 2000mg Pkg[sup -1] applied as NH[sub 4]H[sub 2]PO[sub 4]. Recovery was measured as the increase in Olsen P after 30, 60, and 150 days. P forms were also studied at these times, using sequential chemical extraction. Recovery of applied P decreased with increase in initial Olsen P (P status), Ca saturation, and sulphate concentration in the 1:1 soil extract. Less than 10% of applied P was recovered as Olsen P from the soils with highest P status and Ca saturation (LB2, LB5) after 30 days at the lower fertilizer P rate. P recovered from soils with an initial low Olsen P and high Na saturation (LB3 and LB4) was much higher (more than 50% in LB4 at 30 days at the two P rates). The addition of gypsum increased recovery of applied P (measured as Olsen P) in soils with a high degree of reclamation (high Olsen P and high Ca saturation): in LB2 and LB5, the recovery was double in samples amended with gypsum at 100g kg[sup -1] than in nonamended samples at 150 days. By contrast, recovery of applied P was decreased by gypsum in soils with high Na saturation and an initial low P status. The effect of gypsum on recovery in high P - high Ca soils is related to an interference of sulphate with sorption processes that reduces short-term P sorption and increases the proportion of applied P that precipitates as soluble (bicarbonate extractable) phosphates in the long run. The effect of gypsum on recovery in low P (high Na saturation) soils is due to the increased P sorption capacity resulting from increased Ca saturation. Gypsum amendments increase the efficiency of fertilizer P, contributing to enhanced productivity of freshly reclaimed saline and sodic marsh soils. [ABSTRACT FROM AUTHOR]

Examines the phosphate and sulfate sorption capacities of several Spanish Spodosols with albic horizon. Molar ratios of organic carbon; Characteristics of soil used in the study; Identification of the infrared spectra of untreated soil samples from spodic horizons.