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We present an update to the Granada–Amsterdam Light Scattering Database (https://scattering.iaa.es/), which includes experimental data from both the IAA-Cosmic Dust Laboratory in Granada and the Amsterdam light scattering setup. The updated version features an expanded collection of samples and a more user-friendly interface. We have extended the size range of our mineral samples to mm-cm-sized single particles. Additionally, we have added the diffuse reflectance spectra of some of our powder samples and, from these spectra, obtained the corresponding refractive indices (200 nm–2000 nm). We have also incorporated synthetic scattering matrices defined across the entire scattering angle range (0° to 180°) for most of the powder samples contained in the database. Data in the database are freely available under the request of citation of this paper and the paper in which the data are published. • Open Access Light scattering database. • Experimental scattering matrices hydrosols, terrestrial aerosols, cosmic dust. • Dust samples full characterization: size distributions, Optical/SEM images, refractive indices. • Powders diffuse reflectance spectra and refractive indices (200–2000 nm). • Synthetic scattering matrices. [ABSTRACT FROM AUTHOR]

The increased population has accelerated pavement deterioration of and boosted production of residues, generating a constant environmental problem. One of the main problems of pavements is a failure to develop union between bituminous mastic ligand and aggregate. The following study evaluates the use of ash from cellulose incineration as a contribution filler to improve thermal susceptibility of pavements in different climatic zones. The applied methodology for dosage was based on volumetric criteria and state curves. The obtained results showed that reusing this residue in determined conditions (C v /C s  ≤ 1) offers lower wear loss to 35% of temperatures between −10 and 60 °C, due to the C v /C s  = 0.75 ratio that maximizes the cohesive properties of the mixture. Therefore, we showed that this type of industry residue can be reused without complication in zones of certain climatic criteria and that it provides improved properties to the asphalt mix compared to conventional mixes. [ABSTRACT FROM AUTHOR]

We present measurements of the complete scattering matrix as a function of the scattering angle of a sample of calcite particles. The measurements are performed at 647nm in the scattering angle range from 3° to 177°. To facilitate the use of the experimental data we present a synthetic scattering matrix based on the measurements and defined in the full range from 0° to 180°. The scattering matrix of the calcite sample is modeled using the discrete-dipole approximation. Two sets of shapes, flake-like and rhomboid-like particles giving a total of 15 different targets are considered since both types of shapes have been found in our calcite sample. In our computations we use the measured size distribution of the calcite sample truncated at 1.2μm. We present a theoretical study of the impact of birefringence on the computed scattering matrix elements for both sets of shapes. Four different cases regarding the composition of the calcite particles are considered: two isotropic cases corresponding to the ordinary and extraordinary refractive index of calcite, respectively; one equivalent isotropic case analogous to internal mixing; and birefringence fully accounted for. Numerical simulations are compared with the experimental data. We find that birefringence has little impact on the calculated phase functions but it has a significant effect on the polarization-related elements of the scattering matrix. Moreover, we conclude that the shape of the targets (flakes or irregular rhomboids) has a much stronger effect on the computed scattering matrix elements than birefringence. [ABSTRACT FROM AUTHOR]

Abstract: The Amsterdam Light Scattering Database proved to be a very successful way of promoting the use of the data obtained with the Amsterdam Light Scattering apparatus at optical wavelengths. Many different research groups around the world made use of the experimental data. After the closing down of the Dutch scattering apparatus, a modernized and improved descendant, the IAA Cosmic Dust Laboratory (CoDuLab), has been constructed at the Instituto de Astrofísica de Andalucía (IAA) in Granada, Spain. The first results of this instrument for water droplets and for two samples of clay particles have been published. We would now like to make these data also available to the community in digital form by introducing a new light scattering database, the Amsterdam–Granada Light Scattering Database (www.iaa.es/scattering). By combining the data from the two instruments in one database we ensure the continued availability of the old data, and we prevent fragmentation of important data over different databases. In this paper we present the Amsterdam–Granada Light Scattering Database. [Copyright &y& Elsevier]

Abstract: In this paper we present an overview of light scattering experiments devoted to measure one or more elements of the scattering matrix as functions of the scattering angle of ensembles of randomly oriented small irregular particles in air. A summary of the most important findings in light scattering experiments on ensembles of randomly oriented particles in air is given. The particles of interest are relevant for studies of atmospheres of planets and satellites and also for other astronomical bodies and environments. Some applications of light scattering experiments are also presented. [Copyright &y& Elsevier]

Abstract: A longitudinal study on spatial and temporal behavior of particles less than 2.5μm (PM2.5), solvent extracted organic matter (SEOM), polycyclic aromatic hydrocarbons (PAH), n-alkanes and nitro-PAH was carried out for a full year in 2006, at five sites simultaneously around the Metropolitan Zone of Mexico Valley (MZMV). There is rather uniform distribution of PM2.5 and SEOM in the MZMV regarding gravimetric mass concentration, while some specific organic chemical components showed mass heterogeneity. The highest mass concentrations of target compounds occurred in the dry seasons with respect to the rainy season. Bonfires and fireworks are probably responsible for extreme values of PM2.5, SEOM and PAH (≥228gmol−1). Benzo[ghi]perylene was the most abundant PAH, with C24–C26 the most abundant n-alkanes and 2-nitrofluoranthene and 9-nitroanthracene the most abundant nitro-PAH. The northeast zone was the area with the greatest presence of sources of incomplete diesel combustion, while the central for gasoline combustion. In the southwest, the biogenic sources were more abundant over the anthropogenic sources. This was opposite to the other sites. Factor analysis allowed us to relate different compounds to emitting sources. Three main factors were associated with combustion, pyrolysis and biogenic primary sources while the other factors were associated with secondary organic aerosol formation and industry. Correlation analyses indicated that SEOM originates from different primary emission sources or is formed by different processes than the other variables, except in southwest. Associations among variables suggest that PM2.5 in the northwest and in the southeast originated mainly from primary emissions or consisted of primary organic compounds. PM2.5 in the northeast, central and southwest contains a greater proportion of secondary organic compounds, with the less oxidized organic aerosols in the northeast and the most aged organic aerosol in the southwest. This follows the trends in the prevailing wind directions in MZMV during 2006. [Copyright &y& Elsevier]

Abstract: Seven symmetry relations, with a wide range of validity, are presented for the phase matrix of horizontally oriented particles. Three of these relations constitute a fundamental basis from which four others can be derived by making combinations. All seven relations can be used for many types of particles, including hexagonal plates and columns as well as spheroids, cylinders and cubes. Some applications are also pointed out. [Copyright &y& Elsevier]

Abstract: We present a new apparatus for measuring the complete scattering matrix as a function of the scattering angle of dust irregular particles. The design is based on the well-known apparatus located in Amsterdam, The Netherlands. In this improved version we have extended the scattering angle ranging from 3° to 177°. Moreover, the measurements are performed with a tunable argon–krypton laser that emit at a wavelength of 483, 488, 520, 568, or 647nm. The apparatus has been developed at the Instituto de Astrofísica de Andalucía (IAA), Granada, Spain. To measure the scattering matrix elements we use a number of different optical components such as polarizers, a quarter-wave plate, and an electro-optic modulator. These components are used to manipulate the polarization state of light. By using eight different combinations for the orientation angles of the optical components, all scattering matrix elements are obtained as functions of the scattering angle. The accuracy of the instrument is tested by comparing the measured scattering matrices of water droplets at 488, 520, and 647nm with Lorenz–Mie calculations for a distribution of homogeneous water droplets. [Copyright &y& Elsevier]

Abstract: We present a concise survey of light scattering by small particles in the atmospheres and surface layers of various Solar System bodies, comets, the interplanetary medium, and in planetary rings. Current issues and recent developments are emphasized. Special attention is given to experimental and numerical approaches for solving problems of light scattering by non-spherical particles. References to more detailed papers, websites and books are presented. Key areas for further research are pointed out. [Copyright &y& Elsevier]

Abstract: A systematic study aimed at searching the physical parameters characterizing cometary dust grains that best fit the observations has been conducted. Although it has long been assumed that the cometary dust is mainly composed of strongly absorbing aggregates having monomers of about a tenth of a micrometer in size, all the properties shown by cometary dust particles, particularly those related to phase angle variation of intensity and degree of linear polarization, and their color dependences, have not yet been simultaneously reproduced to date. In this paper we demonstrate that size distributions of moderately absorbing, irregularly shaped, and compact particles of various degree in shape complexity, constitute an alternative approach to explain the observed properties of cometary dust. Aggregate structures produce a much larger degree of linear polarization for incident unpolarized light at side angles than particles having a more compact structure when compared with polarimetric observations of comets. [Copyright &y& Elsevier]

Abstract: We present an update of the Amsterdam Light Scattering Database located at http://www.astro.uva.nl/scatter. We give a detailed explanation and clarification of the nature of the scattering matrices in the database. Measured scattering matrix elements are presented as functions of the scattering angle, for aerosol particles in random orientation at 632.8nm. They pertain to seven volcanic dust samples from three different volcanoes, two samples with extreme refractive indices (hematite and rutile), and three forsterite samples with identical compositions, but different size distributions. For 15 phytoplankton species and two types of silt suspended in water, the database now contains two matrix elements, and as functions of the scattering angle at 632.8nm. Lastly, we have included all scattering matrix elements as functions of the scattering angle for spherical micron-sized water droplets, which may be used for testing purposes. [Copyright &y& Elsevier]

Abstract: We present measurements of the complete scattering matrix as a function of the scattering angle of three different samples of forsterite particles in random orientation at a wavelength of 632.8nm. The three samples were prepared so that three different size distributions were obtained. The composition and reflection spectra of the three samples have been experimentally determined. The results indicate that the elements of the scattering matrix are affected in a different way by the size differences. Since light scattering by comets is probably caused by particles similar to our forsterite particles, the results potentially contain information on the size of the cometary particles. [Copyright &y& Elsevier]

We present a new extensive database containing experimental scattering matrix elements as functions of the scattering angle measured at 441.6 and 632.8 nm for a large collection of micron-sized mineral particles in random orientation. This unique database is accessible through the World-Wide Web. Size distribution tables of the particles are also provided, as well as other characteristics relevant to light scattering. The database provides the light scattering community with easily accessible information that is useful, for a variety of applications such as testing theoretical methods, and the interpretation of measurements of scattered radiation. To illustrate the use of the database, we consider cometary observations and compare them with (1) cometary analog data from the database, and (2) with results of Mie calculations for homogeneous spheres, having the same refractive index and size distribution as those of the analog data. [Copyright &y& Elsevier]

The preparation of pectic enzymes are used for a more efficient extraction of desirable red grape pigments and other compounds which are bound in plant cells and can be faster released by the action of pectic enzymes; shorten the time of maceration, setting, and filtration. The main objective of the present study was to investigate the enzymatic extraction of anthocyanic pigments from the residue remaining after the vinification process of three varieties of Vitis vinifera from Central Chile. The best results of extraction of anthocyanins can be obtained with Vinozym EC using skin grape Ribier after 2 h of treatment. [Copyright &y& Elsevier]

The presence of organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs) was analysed in air particulate matter ≤ 2.5 μm (PM 2.5) and ≤10 μm (PM 10) collected in the Metropolitan Zone of Mexico Valley (MZMV), during 2013 and 2014, respectively. Spatial and seasonal distributions of PM and their organic content named solvent extracted organic matter (SEOM) were determined. PM mass concentration and SEOM/PM ratios were compared with previous studies in 2006 in Mexico City. PM 2.5 concentration was like found in 2006, however, PM 10 decreased ∼43%. The SEOM/PM 10 ratio was kept constant, suggesting a decrease in SEOM as well as PM 10 emitted from natural sources, probably as a result of changes in the land use due to urban growth. A decrease ∼50% SEOM/PM 2.5 ratio was observed in the same period, linked to adequate strategies and public policies applied by the local and federal governments to control the organic matter emitted from anthropogenic sources. Seven out of sixteen OCPs and five out of six PBDEs were found. The most common POPs were endosulfan I, endosulfan II, endosulfan sulfate, BDE-47 and BDE-99, present on >90% of the sampling days. OCPs in PM 2.5 and PBDEs in PM 10 showed seasonal variability. Higher PBDEs concentration in both particle sizes were observed at east and southeast of the MZMV, where one of the biggest landfills and wastewater treatment plants are located. OCPs in PM 10 were mainly emitted from agricultural areas located to the southwest, southeast and east of the MZMV. OCPs in PM 2.5 showed a regional contribution from the north and introduced into the valley. OCP degradation products were dominant over native OCPs, indicating no fresh OCP use. POPs comparison with other cities was made. Agreements and commissions created by the Mexican government reduced OCPs emissions, however, more effort must be made to control PBDE emission sources. Image 1 • OCPs and PBDEs were analysed in the organic matter of PM 2.5 and PM 10 in Mexico Valley. • Adequate strategies and programs have been applied by the Governments to reduce the use of OCPs, as well as the organic matter emitted by combustion sources by Adequate public policies reduced the use of OCPs, as well as the organic matter emitted by combustion sources. • Endosulfan I, endosulfan II, endosulfan sulfate, BDE-47 and BDE-99, were present in >90% of the sampling days. • PBDEs were mainly emitted by landfill and WWTP, while OCPs by agricultural areas and regional contribution. • OCPs degradation products were dominant over native OCPs, indicating no fresh OCPs use. PBDEs and OCPs in PM 2.5 and PM 10 in an urban area. Adequate public policies to increase air quality related to unregulated organic air pollutants. [ABSTRACT FROM AUTHOR]

The rapid development that our society is experiencing effects road management, therefore developing economical and efficient solutions, as well as extending road service life is indispensable. Aging is a problem associated to the majority of failures at the pavement surface layer (cracks, fissures, fatigue), including those produced by traffic solicitations. Diverse studies indicate that alterations to mixtures due to age can be decreased by incorporating a filler or mineral filler. Therefore, the present study incorporates cellulose ashes at different Cv/Cs concentrations as contribution filler in bituminous mastic, analysing its influence on aging resistance using the Cantabro wear test. The results indicated that using cellulose ash as contribution filler allows promising results to be obtained in regards to aging resistance of asphalt mixtures, if they are incorporated in concentrations close to or equal to the critical concentration, with an increase in aging resistance from 45.3 to 48.6% depending on the type of bitumen used. Therefore, incorporating them into the design of asphalt mixtures could be an efficient and economical solution to the current problems of early cracking and pavements with a service life lower than the estimated, although a more thorough analysis of its behaviour in other tests and service conditions is required in bituminous mixtures. [ABSTRACT FROM AUTHOR]

Abstract: Three different pollination syndromes (bee, hummingbird and moth-pollination syndromes) have been described for the different species of the genus Schizanthus Ruiz & Pav. (Solanaceae). Two closely related species from a phylogenetic point of view, Schizanthus grahamii and Schizanthus hookeri, show hummingbird and bee-pollination syndromes, respectively. One of the traits used to assign these pollination syndromes is the colour of the petals, which is red in S. grahamii and bluish-pink in S. hookeri. The objective of this work was to establish the differences in the anthocyanin composition of these two Schizanthus species that contribute to the different pollination syndrome. Identification of the pigments was carried out from the chromatographic and spectral data supplied by the HPLC-DAD-MS n analyses of the samples. Alkaline and acid hydrolyses were also performed in the extracts and in some isolated compounds in order to confirm the identities. First difference between these two species was found in the total anthocyanin content, which was about 13-fold higher in S. grahamii than in S. hookeri. Furthermore, the major peak was also different in both cases, thus explaining quantitative and qualitative colour differences between species. Delphinidin 3-O-rutinoside represented ca. 72% of the total area in S. grahamii and petanin (Petunidin 3-O-p-coumaroylrutinoside-5-O-glucoside) accounted for almost 62% of the total area in S. hookeri. The presence of the p-coumaroylrutinosyl moiety in the petanin makes the intramolecular copigmentation possible, thus conferring the bluish-pink hue to the petals of S. hookeri. Delphinidin 3-O-rutinoside is in turn responsible for the red colour exhibited by the petals of S. grahamii and along with other floral traits, responsible for the attraction of hummingbirds to the plant. Pigments structurally related to petanin, which have been often detected in other genus of Solanaceae, were detected in both species and in similar contents, supporting results from previous studies that pointed to a bee-pollinated common ancestor for both species that further specialised acquiring traits attractive to hummingbirds and among them, red colour of the petals which is mainly supplied by delphinidin 3-O-rutinoside. [Copyright &y& Elsevier]