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981.
Nguyen Tien Phong Mohamed H. Gabr Le Hoai Anh Vu Minh Duc Andrea Betti Kazuya Okubo Bui Chuong Toru Fujii 《Journal of Materials Science》2013,48(17):6039-6047
In this study, core–shell rubber (CSR) nanoparticles with approximate particle size of 35 nm were used as a modifier for the epoxy polymer. The effects of various CSR contents in the epoxy matrix on mode I interlaminar fracture toughness, tensile strength, and fatigue life of the carbon fabric reinforced epoxy (CF/EP) composites were investigated. The experimental results showed that the mode I interlaminar fracture toughness at crack initiation and propagation significantly improved by 71.21 and 58.47 %, respectively, when 8.0 wt% CSR was dispersed in the epoxy matrix. The fatigue life of the modified CF/EP composites at all of CSR contents dramatically increased 75–100 times longer than that of the unmodified CF/EP composites at high cycle fatigue while tensile strength slightly increased by about 10 %. Field emission scanning electron microcopy (FESEM) observations of the fracture surfaces were conducted to explain failure mechanisms of CSR addition to the CF/EP composites. The evidences of the rubber nanoparticle debonding, plastic void growth, and microshear banding were credited for delaying the onset of matrix crack, and reducing the crack growth rate, as a result, attributed to increase in the mechanical properties of the CF/EP composites. 相似文献
982.
Paula Brown Richard Jay Andrea Fox Matthew Oliver 《Hemodialysis international. International Symposium on Home Hemodialysis》2013,17(3):444-449
Heparin‐induced thrombocytopenia (HIT) is a potentially life‐threatening condition that can develop after exposure to unfractionated or low–molecular‐weight heparins. Treatment options appear to be limited in patients on concurrent intermittent hemodialysis. We report the case of an 88‐year‐old man newly initiated on high‐flux hemodialysis who developed HIT and extracorporeal circuit thrombosis after 3 weeks of exposure to unfractionated heparin. Our patient was successfully treated with fondaparinux 2.5 mg subcutaneously three times per week and citrate during dialysis sessions. Antifactor Xa levels were measured on several occasions while receiving fondaparinux. 相似文献
983.
Daniele Chiappe Andrea Toma Francesco Buatier de Mongeot 《Small (Weinheim an der Bergstrasse, Germany)》2013,9(6):913-919
A self‐organised approach for the synthesis of transparent metal nanowire arrays is based on defocused ion beam sputtering. The nanowire arrays, supported on low‐cost dielectric substrates (glass slides), feature a dual functionality: they exhibit anisotropic conductivity, with sheet resistances which are reduced in comparison to those of transparent conductive oxides, and additionally they support localised plasmon resonances. The latter represents an attractive feature in view of plasmon enhanced photon harvesting applications, in which the nanostructured metal electrodes are employed as an alternative to conventional transparent conductive oxides. 相似文献
984.
Cosimo Guerra Andrea Lanzini Pierluigi Leone Massimo Santarelli Davide Beretta 《International Journal of Hydrogen Energy》2013
The performance of a tubular Ni/YSZ anode supported SOFC directly fed by an anaerobic digestion simulated biogas, with an extra addition of carbon dioxide to operate in conservative operating conditions to avoid coking on the anode support, was investigated. The fuel cell has been tested at a fixed oven temperature of 800 °C and under biogas/CO2 mixtures with different volumetric ratios, fuel utilization (FU) and current densities. Polarization curves and performance maps were obtained to better understand the influence of the investigated operational parameters on the cell behavior. Furthermore, since the tubular geometry enables an easy separation of the anode and cathode exhaust gases, the anode off-gas has been collected and monitored through a gas-chromatograph under open circuit voltage to investigate on the catalytic behavior of a Ni-based state-of-the-art anode. For corresponding operative conditions, performances of the cell for biogas/CO2 1/1.5 (i.e. CH4/CO2 30/70) and 1/2 (i.e. CH4/CO2 24/76) were at least 2% and 4% lower than the case 1/1 (i.e. CH4/CO2 20/80), respectively. The highest efficiency of 43.4% was reached at 17.5 A and FU = 70%. 相似文献
985.
The electrooxidation of indoline was studied as the first step in exploring its utility as a model liquid hydrogen carrier. Electrochemical oxidation of indoline in the presence of nitrogen-containing bases resulted in a cathodic shift in the onset of the oxidation. A linear correlation was found between the pKa of the base and the magnitude of the cathodic shift of indoline oxidation. A hydrogen bonding complex model is proposed to account for this effect, and 1H NMR spectroscopy and cyclic voltammetry experiments were conducted to support this proposed mechanism. 相似文献
986.
Silvia Barella Davide Mombelli Andrea Gruttadauria Enrico Laghi Vito Ancona 《钢铁冶炼》2013,40(8):721-724
The decarburisation in the basic oxygen furnace is certainly the chemical process ruling the conversion of pig iron into steel and for the production of high deep drawability steel s. At the end of conversion, the steelmakers have often to blow again to achieve the targeted low values of carbon concentration. This further blowing process implies a productivity loss, even it is not strictly needed because the self-bubbling of the metal bath due to the CO formation can allow setting the carbon concentration within the required chemical range. Actually, due to the high temperatures and oxygen activity at the end of the blowing process, the decarburisation process keeps moving up to the equilibrium. The present study describes and validates a chemical-physical model based on thermodynamic and kinetic aspects that allow the steelmakers to forecast when exploiting the self-bubbling phenomenon avoiding the re-blow, increasing the productivity and the refractories working life. 相似文献
987.
Simone Mannori Valerio Sermenghi Marco Utili Andrea Malavasi Daniel Gianotti 《Fusion Engineering and Design》2013,88(6-8):687-691
The EBBTF (European Breeding Blanket Test Facility) experimental plant is a key component for the development of the breeding blankets (TBMs test blanket modules, HCLL helium cooled lithium lead and HCPB helium cooled pebble bed types) used by ITER. EBBTF is an experimental plant which provides the double breeding/cooling loops (liquid metal and gas) required for HCLL testing. EBBTF is composed of four subsystems (TBM, IELLLO integrated European lead lithium loop, HE-FUS3 helium fusion loop, version 3 and helium compressor build by ATEKO) with dedicated control systems realized with hardware/software combinations covering 15 years (1995–2010) time span. At the end of 2010 we began to upgrade the HE-FUS3 data acquisition control systems (DACS) replacing the obsolete PLC Siemens S5 with National Instruments Compact FieldPoint and LabVIEW. The control room has been completely reorganized using high resolution monitors and workstations linked with standard Ethernet interfaces. The data acquisition, control, safety and SCADA software has been completely developed in ENEA using LabVIEW. In this paper we are going to discuss the technical difficulties and the solutions that we have used to accomplish the upgrade. 相似文献
988.
Gian Piero Celata Francesco D’Annibale Andrea Mariani Luca Saraceno Rosaria D’Amato Roberto Bubbico 《传热工程》2013,34(13):1060-1072
The article reports the results of heat transfer experimental tests on water-based TiO2 (9 wt%) and SiC (3, 6, 9 wt%) nanofluids. Measurements were performed in a two-loop test rig for immediate comparison of the thermal performances of the nanofluid with the base fluid. The convective heat transfer is evaluated in a circular pipe heated with uniform heat flux (from 20 to 240 kW/m2) and flow regimes from laminar to turbulent. Tests have been performed to compare the heat transfer of nanofluids and water at the same velocity (from 0.7 to 1.6 m/s) or Reynolds number (from 300 to 6000), and they have also been compared with values calculated from some of the most widely used correlations. The analysis of the experimental data shows a strong dependence on the parameter used, while both the nanofluid and water data have the same agreement with the calculated values. Nanofluids were manufactured through a two-step procedure: laser synthesis of nanoparticles followed by dispersion in water. 相似文献
989.
Anna Osello Andrea Acquaviva Chiara Aghemo Laura Blaso Daniele Dalmasso David Erba Giovanni Fracastoro Damien Gondre Marco Jahn Enrico Macii Edoardo Patti Anna Pellegrino Paolo Piumatti Ferry Pramudianto Jerôme Savoyat Maurizio Spirito Riccardo Tomasi Joseph Virgone 《Energy Efficiency》2013,6(4):707-723
In this paper, we report a methodology, developed in the context of Smart Energy Efficient Middleware for Public Spaces European Project, aimed at exploiting ICT monitoring and control services to reduce energy usage and CO2 footprint in existing buildings. The approach does not require significant construction work as it is based on commercial-off-the-shelf devices and, where present, it exploits and integrates existing building management systems with new sensors and actuator networks. To make this possible, the proposed approach leverages upon the following main contributions: (a) to develop an integrated building automation and control system, (b) to implement a middleware for the energy-efficient buildings domain, (c) to provide a multi-dimensional building information modelling-based visualisation, and (d) to raise people’s awareness about energy efficiency. The research approach adopted in the project started with the selection, as case studies, of representative test and reference rooms in modern and historical buildings chosen for having different requirements and constraints in term of sensing and control technologies. Then, according to the features of the selected rooms, the strategies to reduce the energy consumptions were defined, taking into account the potential savings related to lighting, heating, ventilation, and air conditioning (HVAC) systems and other device loads (PC, printers, etc.). The strategies include both the control of building services and devices and the monitoring of environmental conditions and energy consumption. In the paper, the energy savings estimated through simulation, for both HVAC and lighting, are presented to highlight the potential of the designed system. After the implementation of the system in the demonstrator, results will be compared with the monitored data. 相似文献
990.
Andrea Turoňová Miriam Gálová Matilda Gernátová 《Particulate Science and Technology》2013,31(2):126-135
The electrolytic deposition of an electropositive metal is often accompanied by electroless deposition. However, this process is very difficult to control. For that reason, our study has been aimed at the conditions of the electroless deposition of copper coating onto the iron powder particles from sulphate electrolyte. The process consists of two partial reactions; solid iron substrate dissolves into the solution, thus providing the electrons necessary for reduction of copper. The course of the electroless process depends to a large extent on the composition and pH of the electrolyte as well as on the size and concentration of the iron powder particles in the electrolyte. In order to suppress the spontaneous electroless deposition of copper, sodium citrate as complexing agent was used. The following parameters were determined to characterize the reaction course: the heterogeneous rate constant of Fe powder dissolution and degree of Fe conversion as well as thickness of the Cu layer on the Fe powder, both of the latter evaluated upon attaining the stationary state. The main influence exhibited on the reaction course is the efficient surface area available for electroless deposition. 相似文献