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In concentrating solar power plants, mirrors are used to redirect solar radiation onto a receiver. The optical yield of a plant is related to the mean value of the near-specular reflectance in the range of interest of incidence and acceptance angles for that plant. To avoid the need for an exhaustive measurement of the solar mirror at various incidence and acceptance angles, a predictive method based on the Equivalent Model Algorithm for Solar Mirrors was recently proposed. Whilst developed for clean surfaces, unfortunately that model is inaccurate for soiled solar mirrors. In this paper, an additional model to describe the spectral reflectance loss caused by soiling of solar mirrors is presented and successfully tested on a set of artificially and naturally-soiled specimens. The model is based on absorption, scattering and diffraction. Its parameters are obtained by best-fitting a set of experimental hemispherical and near-specular reflectance spectra, both in soiled and cleaned state. The best-fit software developed is now published as open source software, providing access also to non-specialized users. The model also allows to correlate simple handheld reflectometer readings used in the solar field (with typically limited spectral and acceptance angle information) to the most meaningful parameter determining the plant yield: the solar-weighted near-specular spectral reflectance of the soiled reflector. Such correlations are specific for the plant, the kind of local dust and the chosen portable reflectometer. • Soiling reduces Sun-Conic-Reflectance of solar mirrors, and optical yield of CSP plants. • Predictive way to evaluate SCR fails for soiled solar mirrors. • A soiling model based on absorption, scattering and diffraction is here presented. • The model was successfully tested on several artificially and naturally soiled mirrors. • The model allows to relate single-wavelength readings to SCR of concern for the plant. [ABSTRACT FROM AUTHOR]

Abstract Palynological research carried out on two renowned archaeological sites located in central Sicily allows the reconstruction of agrarian landscapes in Late Antiquity. The palynological investigations may improve the resolution of vegetational-environmental events recorded from extra-local palynological sequences by giving information on local plant landscape and human influence in the region. The stratigraphy uncovered from these archaeological sites features very high resolution. Villa del Casale of Piazza Armerina, a monumental villa included in the UNESCO World Heritage List, and the near 'agro-town' Philosophiana are key sites to look for the effects of countryside exploitation in the Roman world. They were extraordinary rural complexes from the Roman to Medieval periods. Their long chronology offers the opportunity to investigate land use and economy transformations that occurred in the area at the transition from Late Antiquity to the Middle Ages. The palynological research has been carried out on 40 samples, including archaeological samples dated from the end of 3rd to 7th century AD, and one moss polster collecting present pollen rain. Ornamental and shade plants were concentrated in the luxury villa, while fruit trees and agrarian activities were more evident in the next farmhouse. Late Antiquity is proved to be a critical period of both transition between different cultures and landscape transformations that have lead the past vegetation to the modern landscape of this island. Nevertheless, pollen suggests a continuity of the agrarian landscape during this period. Although changes had occurred, subsequent cultures were progressively incorporated in the agrarian-pastoral landscape management. [ABSTRACT FROM AUTHOR]

Solar reflectors for Concentrating Solar Technologies require a high reflectance in the terrestrial solar spectrum (280–4000 nm). Besides the wavelength, the reflectance of solar mirror materials is also dependent on the incidence angle of the incoming sunlight. The commonly used measurement equipment measures the reflectance at fixed near-normal incidence angles, typically between 8° and 15°. In this work, the annual incidence angle frequency distribution has been calculated for a LS3/Eurotrough-type parabolic-trough collector located at different sites, and for the heliostat field of the solar tower system CESA-1 located at the Plataforma Solar de Almería in Tabernas, southern Spain. It was found that the most frequent incidence angles registered in the solar field are quite higher than the ones at which reflectance is measured with state of the art instruments, obtaining mean incidence angles in the range of 28–35° depending on the type and location of the solar field. A methodology to predict the off-normal reflectance of silvered-glass mirrors based on near-normal reflectance and transmittance measurements of the uncoated glass is presented. The complex refractive index of 2, 4 and 5 mm thick solar glass and the deposited silver was determined and used to model the solar weighted reflectance of silvered-glass mirrors at different incidence angles. The model was compared to experimental measurements. For this purpose, the Spectral Specular Reflectometer (S2R) has been improved and updated with a polarizer crystal to measure reflectance at perpendicular (s-pol) and parallel (p-pol) polarizations up to incidence angles of θ = 70°. Eight solar mirror materials (three silvered-glass mirrors of different glass thicknesses, two anti-soiling coated glass mirrors, two enhanced aluminum reflectors and a silvered polymer film) have been measured over a broad range of incidence angles and the results have been weighted with the annual incidence angle frequency distribution. The obtained incidence angle-weighted reflectance is a suited parameter to compare the efficiency of solar mirror materials taking into account their use in a specific collector type and location. [ABSTRACT FROM AUTHOR]

The article presents how to innovate a product using information extraction from patents literature to identify and overcome TRIZ contradictions. Each initial inventive situation has to be formulated in terms of contradictions in order to use the most effective tool for problem solving provided by the TRIZ theory. The authors propose, (1) an algorithm guiding the user to move from an indefinite problem situation to obtain a clearer problem formulation, following a process inspired to the ARIZ approach for fixing physical contradictions, and (2) some strategies and tools for selecting, acquiring and finally modeling the necessary information to improve the effectiveness in building the contradiction model. All those strategies have been implemented in a knowledge management tool called KOM, working as an automatic patent searching engine based on a functional oriented search. An exemplary application is presented to explain how KOM is integrated in the problem definition process. [ABSTRACT FROM AUTHOR]

This paper introduces a patent searching framework to assess the state of the art of a product or a technology and to support technology transfer activities. It combines several dimensions (IPC, Object & Behaviour/Function keywords) together with an integrated abstraction methodology based on WordNet/Multi-screen in order to systemize and facilitate FBOS (Function/Behaviour–Oriented Search). The core of the method is the abstraction of behaviour (based on a semantic approach) resulting in keywords at different abstraction levels, and a patent search based on these keywords and on a preassembled classification of Physical Effects. Key patents and space opportunities are mapped in a suitable graph, based on a revision of the classical Gero's FBS theory. An exemplary application in the lens sterilization domain shows the functioning of the patent-pending software. [ABSTRACT FROM AUTHOR]

Solar power generation has been gaining worldwide increasing interest by virtue of its ability to meet both the growing energy needs and the increasing concerns on the carbon dioxide emissions. One of the most promising Concentrated Solar Power (CSP) technologies under development uses a parabolic dish to concentrate solar power into a focal point, raising thetemperature of a working fluid which is then used in a thermodynamic cycle to generate electricity. In the OMSoP project, funded by the European Commission, it is proposed to use a Brayton cycle in the form of a micro-gas turbine (MGT), which replaces the more conventional Stirling engine,with the aim of increasing the ratio of the electric power generated to the solar energy collected and improving the operability in relation to solar energy short time fluctuations. To achieve these objectives, research and development will be conducted in all aspects of the system leading to a full scale demonstrative plant to be located at the ENEA Casaccia Research Centre.The present work deals with the activities carried out so far by ENEA, which is principally involved in the development and experimental characterization of the dish component, and in the integration of the complete system, both in terms of modelling and realization. [ABSTRACT FROM AUTHOR]

Mirrors are the first link in the energy-conversion chain from Sun to electricity-delivery in the grid. Shape and solar reflectance are the key-parameters of mirrors, respectively affecting how solar radiation is concentrated around the focus, and how much of the impinging solar power is reflected. In SolarPACES Task III, an expert group is drafting the solar reflectance guidelines; in order to speed up the discussion the SRRR round robin was launched at the beginning of 2013. Identical kits, each one consisting of ten specimens collected from eight cooperating producers, were distributed and measured at six research institutes, acting as evaluators. The kit includes both traditional (glass based) and innovative (first-surface) solar mirrors. The paper only reports on the simplest task among those of SRRR: the solar hemispherical reflectance measurement. Near-specular solar reflectance was also measured and compared but the results are still under investigation and are not part of this paper. The measurements were accomplished according to the guidelines. The differences among the achieved results are within the typical accuracy of spectrophotometers, demonstrating the reliability of the reflectance guidelines. The statistic of the deviations from the true value is analysed separately for each evaluator, and allows us to infer information abut the gauging-status of the adopted reference mirror, as well as the measurement reproducibility. [ABSTRACT FROM AUTHOR]

Abstract: Recently a new method for characterization of mirrors for concentrating solar power has been proposed: starting from the hemi- spherical reflectance spectrum and the data obtained with a dedicated experimental set-up, the solar near-specular reflectance at off-normal incidence and in the range 0-20 mrad of (half) acceptance-angle is predicted. The limits of the reflectometers commonly used in specularity study, and the advantages of the new experimental set-up are discussed. The most relevant modifications, among the latest ones carried out in view of the forthcoming set-up commercialization, are described: direct measurement of diffuse re- flectance beyond 20 mrad; adoption of cheaper, more compact, and less coherent lasers; new procedure of data processing to get more reliable coherent-free assessment. [Copyright &y& Elsevier]

Abstract: International patent corpus is a gigantic source containing today about 80million of documents. Every patent is manually analyzed by patent officers and then classified by a specific code called Patent Class (PC). Cooperative Patent Classification CPC is the new classification system introduced since January 2013 in order to standardize the classification systems of all major patent offices. Like keywords for papers, PCs point to the core of the invention, describing concisely what they contain inside. Most of patents strategies are based on PC as filter for results therefore the selection of relevant PCs is often a primary and crucial activity. This task is considered particularly challenging and only few tools have been specially developed for this purpose. The most efficient tools are provided by patent offices of EPO and WIPO. This paper analyzes their PCs search strategy (mainly based on keyword-based engines) in order to identify main limitations in terms of missing relevant PCs (recall) and non-relevant results (precision). Patents have been processed by KOM, a semantic patent search tool developed by the authors. Unlike all other PC search tools, KOM uses semantic parser and many knowledge bases for carrying out a conceptual patent search. Its functioning is described step by step through a detailed analysis pointing out the benefits of a concept-based search vis-à-vis a keyword-based search. An exemplary case is proposed dealing with CPCs describing the sterilization of contact lenses. Comparison could be likewise conducted on other PCs such as International (IPC), European (ECLA) or United States (USPC) patent classification codes. [Copyright &y& Elsevier]

Highlights: [•] Hemispherical-reflectance is measured at normal incidence by a spectrophotometer. [•] Off-normal incidence is predicted by a simplified optical model. [•] Specular reflectance is measured at several λ and acceptance-angle with simple set-up. [•] The knowledge is extended to the whole solar range by modelling the data. [•] Specular solar-reflectance is predicted versus acceptance and incidence angle. [Copyright &y& Elsevier]

Abstract: Sustainability is one of the most recent theme designers have to deal with and sustainability parameters are quickly gaining the top of the list of the requirements any product has to fulfil. Due to standards, legal regulation and customer growing awareness of environmental issues, engineers cannot avoid turning their everyday activities from design to eco-design. By the way, a significant drop of environmental impact of products cannot be achieved by simply adding a „green‟ constraint to the already overpopulated list of design constraints. To answer to this issue a plurality of methods are available helping the designer (or pretending to) to assess product lifecycle or to provide suggestions on how to innovate the product or process according to sustainable goals. Within this context, the present work describes a way of using TRIZ concepts and tools in order to both assess and innovate a technical system so that some practical activities to ensure sustainable results can be easily embodied into everyday design practice. The main novelty on the operative level consists of an original method based on a set of Guidelines derived from Laws of Technical System Evolution (LTSE) in order to assess the value of existing solution (e.g. using Resources and Functionality as a metric of evaluation), to understand the most promising directions of improvement and to improve said solution also according to sustainability requirements. The paper will show the way Guidelines are applied with practical examples and an industrial case study will be presented and discussed. [Copyright &y& Elsevier]

Summary: Background & Aims: To assess prevalence of bone mineral density (BMD) reduction and relationship between bone mineral status and anthropometric assessment, nutritional intake and physical activity in adolescents with early anorexia nervosa (AN). Methods: Fifty-seven consecutive AN patients and 57 healthy controls underwent anthropometric status, bone density, body composition and physical activity evaluations. In AN patients clinical features and nutritional intake were also assessed. Results: Thirty-five patients with AN (62%) and 44 healthy subjects (77%) (pNS) showed normal BMD. Mean value of BMD Z-score was −0.6±0.9 in AN patients and −0.2±1.4 in controls (pNS). Weight at diagnosis and lean mass resulted the main predictor of bone loss but also height, best weight before diagnosis and BMI resulted correlated with bone mineral status in AN patients. Additionally, AN patients maintained good levels of protein intake and sport activity Conclusions: Early diagnosis may prevent bone loss in AN patients. Protein intake and moderate physical activity seem to be useful to maintain an adequate bone mineral status. [Copyright &y& Elsevier]

Abstract: An optical profilometer has been developed based on the idea that the large panels that compose solar-power concentrators and a tolerance threshold for slope-errors to some milliradians, can allow the use of a geometric-optics framework and the investigation of ray-paths by means of a laser beam. The instrument scheme is discussed in detail together with the related problems and the solutions adopted. Data analysis also makes use of an innovative method, based on the iterative application of a criterion about the intersection between the tangents of adjacent points, which allows a realistic profile of the reflector-surface to be drawn. The methodology adopted allows us to call our instrument a profilometer rather than an instrument that gives only information about the tangent of the profile. The instrument accuracy on profile and arctangent deviations from the ideal parabola is 20μm and 15μrad, respectively. The results obtained for a reflecting panel are also reported. [Copyright &y& Elsevier]

The development of electrocatalysts for electrochemical water splitting has received considerable attention in response to the growing demand for renewable energy sources and environmental concerns. In this study, a simple hydrothermal growth approach was developed for the in-situ growth of non-stoichiometric CrO 0.87 and Co 3 O 4 hybrid materials. It is apparent that the morphology of the prepared material shows a heterogeneous aggregate of irregularly shaped nanoparticles. Both CrO 0.87 and Co 3 O 4 have cubic crystal structures. Its chemical composition was governed by the presence of Co, Cr, and O as its main constituents. For understanding the role CrO 0.87 plays in the half-cell oxygen evolution reaction (OER) in alkaline conditions, CrO 0.87 was optimized into Co 3 O 4 nanostructures. The hybrid material with the highest concentration of CrO 0.87 was found to be highly efficient at driving OER reactions at 255 mV and 20 mA cm−2. The optimized material demonstrated excellent durability for 45 h and a Tafel slope of 56 mV dec−1. Several factors may explain the outstanding performance of CrO 0.87 and Co 3 O 4 hybrid materials, including multiple metallic oxidation states, tailored surface properties, fast charge transport, and surface defects. An alternative method is proposed for the preparation of new generations of electrocatalysts for the conversion and storage of energy. • Hydrothermally non-stoichiometric CrO 0.87 and Co 3 O 4 hybrid system was prepared. • CrO 0.87 and Co 3 O 4 hybrid system showed an enhanced OER activity. • A low overpotential for OER reaction was about 255 mV at 20 mA/cm2. • The CrO 0.87 and Co 3 O 4 hybrid system was highly durable for 45 h. [ABSTRACT FROM AUTHOR]

Archaeobotanical analyses (mainly on seeds and fruits – over 1000 l of sieved material with unpublished data) from three urban sites (2nd cent. BC – 2nd cent. AD) provided interesting ethnobotanical information about a Roman colony, Mutina (Emilia-Romagna, Northern Italy), founded in 183 BC. In this paper, comparisons are made between productive areas, landfills and one site that shows the evolution of a rich domus . The information obtained concerns the environment in which the town was born and developed, but especially plant-man relationships (food, crafts, green décor etc.) in a thriving Roman colony in Northern Italy. A good example is provided by analyses carried out in a tank, where the recovery of some archaeozoological finds indicates that it was used for fish farming; this hypothesis is supported by some particular vegetal findings. [ABSTRACT FROM AUTHOR]

Recently, there has been a rise in the interest in nanotechnology due to its enormous potential for the development of new products and applications with higher performance and new functionalities. However, while nanotechnology might revolutionize a number of industrial and consumer sectors, there are uncertainties and knowledge gaps regarding toxicological effects of this emerging science. The goal of this research concerns the implementation into Life Cycle Assessment (LCA) of preliminary frameworks developed to evaluate human toxicity and exposure factors related to the potential nanoparticle releases that could occur during the life cycle steps of a functionalized building material. The present LCA case study examines the ecodesign of nanoTiO 2 functionalized porcelain stoneware tile production. The aim of this investigation is to manufacture new eco-friendly products in order to protect human health and ecosystem quality and to offer the market, materials with higher technological properties obtained by the addition of specific nanomaterials. [ABSTRACT FROM AUTHOR]