5 kWe + 5 kWt reformer-PEMFC energy generator from bioethanol first data on the fuel processor from a demonstrative project

A power unit constituted by a reformer section, a H₂ purification section and a fuel cell stack is being tested c/o the Dept. of Physical Chemistry and Electrochemistry of Università degli Studi di Milano, on the basis of a collaboration with HELBIO S.A. Hydrogen and Energy Production Systems, Patras (Greece), supplier of the unit, and some sponsors (Linea Energia S.p.A., Parco Tecnologico Padano and Provincia di Lodi, Italy). The system size allows to co-generate 5 kW_e (220 V, 50 Hz a.c.) + 5 kW_t (hot water at 65 °C) as peak output. Bioethanol, obtainable by different non-food-competitive biomass, is transformed into syngas by a pre-reforming and reforming reactors couple and the reformate is purified from CO to a concentration below 20 ppmv, suitable to feed a proton exchange membrane fuel cell (PEMFC) stack that will be integrated in the fuel processor in a second step of the experimentation. This result is achieved by feeding the reformate to two water gas shift reactors, connected in series and operating at high and low temperature, respectively. CO concentration in the outcoming gas is ca. 0.4 vol% and the final CO removal to meet the specifications is accomplished by two methanation reactors in series. The second methanation step acts merely as a guard, since ca. 15 ppmv of CO are obtained already after the first reactor.     

Fatty Acid Composition of Freshwater Wild Fish in Subalpine Lakes: A Comparative Study

In this study, the proximate and fatty acid compositions of the muscle tissue of 186 samples of fish belonging to fifteen species of freshwater fish harvested in subalpine lakes (bleak, shad, crucian carp, whitefish, common carp, pike, black bullhead, burbot, perch, Italian roach, roach, rudd, wels catfish, chub and tench) were investigated. Most of the fish demonstrated a lipid content in the fillet lower than 2.0 g 100 g^?1 wet weight (range 0.6–9.7). A strong relationship between feeding behavior and fatty acid composition of the muscle lipids was observed. Planktivorous fish showed the lowest amounts of n‐3 fatty acids (p < 0.05), but the highest monounsaturated fatty acid (MUFA) contents, in particular 18:1n‐9. Conversely, carnivorous fish showed the highest amounts of saturated fatty acids and n‐3 fatty acids (p < 0.05), but the lowest MUFA contents. Omnivorous fish showed substantial proportions of n‐3 fatty acids and the highest contents of n‐6 fatty acids. Principal component analysis showed a distinct separation between fish species according to their feeding habits and demonstrated that the most contributing trophic markers were 18:1n‐9, 18:3n‐3, 22:6n‐3 and 20:4n‐6. The quantitative amounts n‐3 polyunsaturated fatty acid in muscle tissues varied depending on the fish species, the lipid content and the feeding habits. Some species were very lean, and therefore would be poor choices for human consumption to meet dietary n‐3 fatty acid requirements. Nevertheless, the more frequently consumed and appreciated fish, shad and whitefish, had EPA and DHA contents in the range 900–1,000 mg 100 g^?1 fresh fillet.     

Processing of alumina-coated tetragonal zirconia materials and their response to sliding wear

Alumina-coated tetragonal zirconia stabilised with 3 mol% of Y₂O₃ (YTZP) specimens (30 mm × 30 mm × 6 mm) have been obtained by dipping of pre-sintered YTZP compacts in alumina suspensions and subsequent sintering. The coated specimens present hardness values and a wear resistance similar to those of reference dense alumina specimens and significantly higher than those of the YTZP substrates.     

Optimization of pump absorption in MOF lasers via multi-long-period gratings: design strategies

Different strategies for designing optical couplers, optimized to enhance the pump absorption in the rare-earth-doped core of microstructured fiber lasers, are illustrated. Three kinds/configurations of optical couplers have been designed and compared as examples of the different design strategies which can be followed. Their effectiveness to enhance the performance of an ytterbium-doped, double cladding, microstructured optical fiber laser has been accurately simulated. They consist of a suitable cascade of multiple long-period gratings (MLPGs) inscribed in the fiber core region. The characteristics of the MLPG couplers have been simulated via a homemade computer code based on both rate equations and an extended coupled mode theory. The proposed MLPG couplers seem particularly useful in the case of low rare-earth concentration but, even for a middle-high ytterbium concentration, as N(Yb)=5×10(25) ions/m(3), the slope efficiency S can be increased up to 20%, depending on the fiber length.     

In vitro fertilisation with frozen-thawed bovine sperm sexed by flow cytometry and validated for accuracy by real-time PCR

The methodologies used for cytometric sorting of fresh spermatozoa never allowed a clear resolution of sexual chromosomes of frozen-thawed semen. To devise a novel method for the production of bovine predefined sexed embryos using frozen-thawed semen, sorting efficiency of different protocols was studied using a new quantitative real-time PCR method to verify the purity of sexed semen. To this aim, after Percoll separation, frozen-thawed samples were stained at different temperatures and concentrations of Hoechst 33342 using a short-incubation time. The concentration of Hoechst 33342 of 500 mug/ml at a temperature of 37 degrees C provided good and stable fluorescence signals. Preventing the sperm clustering by adding 0.6% BSA in the 90% Percoll fraction led to X-bearing sperms purity of 91+/-2%. Thereafter, sorted sperms were used for in vitro fertilisation (IVF). Despite the lower cleavage rates reported in the sorted groups when compared with the control groups (40 vs 48%, P<0.01), blastocyst formation in the sorted and control groups was not different (27 vs 24% of the cleaved respectively). The PCR analysis of 30 blastocysts confirmed 26 embryos to be correctly sexed (87%). Transfer of two embryos per recipient into six synchronised heifers resulted in four pregnancies. Two abortions occurred at day 60, while two pregnancies went to term delivering two female calves. In conclusion, high purity and repeatability of sorting was obtained with frozen-thawed bull semen that was subsequently used for IVF giving rise to viable embryos and offspring. In addition, real-time PCR revealed to be an optimal support for these studies, providing a rapid and reliable estimation of flow cytometric efficiency.     

Impact of Turbidity Currents on Reservoir Sedimentation

All lakes created on natural rivers are subjected to reservoir sedimentation. The construction of a dam significantly modifies the flow conditions of natural streams inside and downstream of an artificial lake. The sediment concentration is often high during the flood season, and the entering flow shows a greater density than the ambient fluid. Suspended load can therefore be carried along the reservoir bottom to the dam in the form of turbidity currents. This paper presents research results that help to better understand this physical phenomenon, which contributes to reservoir sedimentation. It is based on in situ measurements, a laboratory scale model of turbidity currents and numerical flow simulations. The study of a thousand-year flood in the Luzzone Reservoir in the Swiss Alps using the developed computer model revealed the potential of such a tool. In particular, the impact on the sediment deposits was analyzed. A valuable evaluation of the incidence of such a turbidity flow is presented and its effects are compared to observations. Significant progress has been made in understanding the importance of turbidity currents in reservoir sedimentation.     

Surface functionalization of cotton cellulose with glycidyl methacrylate and its application for the adsorption of aromatic pollutants from wastewaters

Cellulose material C1 was prepared by grafting of glycidyl methacrylate (GMA) in the presence of Fenton-type reagent. This one-pot procedure provided C1 with glycidyl isobutyrate branches. Glycidyl epoxide ring opening with water turned C1–C2 material branched with glycerol isobutyrate. So, C1 surface bears hydrophobic branches ending with the glycidyl group, while C2 surface presents hydrophilic branches ending with the glycerol group. The adsorption of aromatic polluting substances like phenol (Ph), 4-nitrophenol (pNPh), 2,4-dinitrophenol (dNPh), 2,4,6-trinitrophenol (picric acid, tNPh) and 2-naphtol (BN) from their water solutions was tested with C1, C2 and with the untreated cellulose material C0. Phenol adsorption did not occur. All the other aromatic molecules were removed in different amount both by C1 and C2. C1 and C2 showed different affinities towards nitrophenols and 2-naphtol. While C1 was much more effective for removing the hydrophobic 2-naphtol, C2 had higher adsorption capacity towards the hydrophilic nitrophenols, in agreement with their branches polarity, respectively.     

The design of a collaborative interface for narration to support reconciliation in a conflict

This paper is about the development of a face-to-face collaborative technology to support shifting attitudes of participants in conflict via a narration task. The work is based on two cultural elements: conflict resolution theory and the design of a collaboration enforcing interface designed specifically for the task. The general claim is that participants may achieve a greater understanding of and appreciation for the other’s viewpoint under conditions that support partaking in a tangible joint task and creating a shared narration. Specifically, a co-located interface for producing a joint narration as a tool for favoring reconciliation is presented and discussed. The process based on this technology implicitly includes classical steps in conflict resolution approaches, such as escalation and de-escalation. Our goal is to show that this interface is effective and constitutes an alternative to a typical face-to-face moderated discussion.     

QoS management middleware solutions for Bluetooth audio distribution

A primary challenge in the mobile Internet scenario is the dynamic differentiation of provided levels of Quality of Service (QoS) depending on client characteristics and current resource availability. In this context, the paper presents how the application-level ubiQoS middleware supports the provisioning of audio applications with different QoS levels over the last Bluetooth segment to wireless devices. To this purpose, ubiQoS dynamically deploys mobile proxies, acting as masters in Bluetooth piconets, to properly configure and manage Bluetooth connections at runtime. Audio applications working on top of ubiQoS can easily exploit differentiated QoS by simply specifying different user classes and terminal profiles. ubiQoS proxies exploit JSR82ext, a newly developed Java library that extends the JSR82 specification for Java-based Bluetooth communication facilities with richer QoS management functions for all types of Bluetooth connections. The reported experimental results show that our Java-based implementation can dynamically support differentiated QoS levels for audio traffic, with an efficient usage of the available Bluetooth bandwidth.     

Simultaneous removal of Cd,Co, Cu,Mn, Ni,and Zn from synthetic solutions on a hemp‐based felt. II. Chemical modification

In this study, we propose a chemical pretreatment to improve the performance of a hemp‐based material in felt form used as an adsorbent for removing the metals from aqueous mixtures of Cd, Co, Cu, Mn, Ni, and Zn. The felt was coated with a maltodextrin‐1,2,3,4‐butane tetracarboxylic polymer in order to provide ion‐exchange properties to the material by introducing carboxylic groups. It was characterized by solid‐state ¹³C‐NMR technique and by energy‐dispersive X‐ray spectroscopy. This new adsorbent was then used in batch experiments and its performances were compared with those of non‐modified hemp. Different controlling experimental conditions have been investigated. Modified hemp exhibited strong adsorption capacities due to a chemisorption mechanism (complexation, ion exchange): up to 25 mg/L (in reality, 150 mg of metals per L), all metals in the solution were removed. A modified hemp dosage of 1 g was able to remove 13.91 mg of metals in 100 mL of solution at a concentration of 25 mg/L for each metal, whereas nonmodified hemp only removed 7.4 mg in the same experimental conditions. Adsorption of metals reached equilibrium in 60 min and the performances were pH‐independent between 3 and 6, but dependent on the presence of NaCl, except for Cu. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45138.