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Abstract: The paper describes the research activities carried out at the CNR Institute for Advanced Energy Technologies “Nicola Giordano”, aimed to develop, assemble and test a hydrogen generator, named HYGen I, to integrate with a PEFC (polymer electrolyte fuel cell) for residential applications. The unit, capable to convert light hydrocarbons (methane, propane, LPG, butane), with a nominal hydrogen production of 2Nm3 h−1 and a maximum hydrogen production of 5Nm3 h−1, can be considered the only prototype of this size in Italy. Preliminary experimental results, with a proprietary Pt/CeO2 catalyst for the autothermal reforming (ATR) and commercial catalysts for intermediate water gas shift (ITWS) and preferential oxidation (PROX) have been reported. [Copyright &y& Elsevier]

One of the more investigated fuel processor subsystems, for polymer electrolyte fuel cell electric vehicles (PEFCV), is the carbon monoxide clean-up step. At present, the research efforts are addressed to develop a system able to reduce, at level acceptable for PEFCs (particularly in transient response), the amount of CO in the stream outgoing of the reformer.A unit, working as post-filter of the CO preferential oxidation (PROX), based on the reversible complex formation and dissociation reaction between CO and CuCl, able to overcome the main limits of the PROX (instantaneous cold-start and dynamic removal of CO in reformate to less than 10 ppm) has been analyzed. The experimental approach of this study has regarded the screening of different supports (Al2O3, carbon, SiO2) and the identification of optimal operating conditions (temperature, pressure, GHSV, adsorption/desorption time). [Copyright &y& Elsevier]

Liquid hydrocarbons conversion into hydrogen rich gas is a central process step in fuel processors for auxiliary power units (APUs) for naval applications. Diesel, together with gasoline, is the preferred fuel for these applications. The CNR-ITAE has developed an hydrogen generator based on steam reforming (SR) of n-dodecane (n-C 12 H 26 ) as surrogate of diesel, designed for a maximum hydrogen production of 1.5 Nm 3 /h. The prototype consists of an integrated catalytic reactor coupled with heat exchanger, static mixer, water–dodecane and recycle reservoirs, manual/automatic valves, pressure regulators/transducers, flow meters, and ancillaries. The unit has been engineered, focusing every single component and the system integration, to meet the requirements of small size and volume, improving thermal/mass transfer and system efficiency. This study reports the performance of the hydrogen generator with a commercial Rh-based catalyst, packed on the steam reforming reactor. Experimental tests were carried out at a molar ratio steam to carbon (S/C) of 2.5, under a gas hourly space velocity (GHSV) of 3500 h −1 , as derived from preliminary investigations in laboratory scale. Total conversion of n-dodecane and absence of carbon deposition phenomena, were observed. The syngas produced (H 2 /CO = 4.7) was adequate to feed a Solid Oxide Fuel Cell (SOFC). [ABSTRACT FROM AUTHOR]

Abstract: This study presents experimental study on a novel methane fuel processing system for hydrogen (H2) production. The unit includes into a single package the autothermal reformer, the CO shift converter, the preferential oxidation reactor and the internal heat exchangers. Effects of operative conditions, related to the H2 productivity, on the performances, were investigated experimentally, in order to evaluate the integration of the fuel processor with a Polymer Electrolyte Fuel Cell (PEFC) system for residential applications. The sensitivity analysis showed that the overall performance is strongly dependent upon the operative conditions considered. [Copyright &y& Elsevier]

Abstract: The performance of a Pt/CeO2 catalyst as packed bed, coated on monolith and as self-structured bed has been evaluated during C3H8 oxidative steam reforming. Structured bed, prepared by a new aqueous tape casting method, combining high total porosity (80%) with a self-supported channel structure, offers a better and more efficient control of heat and mass transfer along the catalytic bed, showing, especially at high gas hourly space velocity (30×104 h−1), better performance in terms of fuel conversion, hydrogen production and low by-products formation coupled with an economy of the catalyst of about to 43% with respect to the traditional packed bed system. [ABSTRACT FROM AUTHOR]

Abstract: Modeling studies have been conducted on Preferential Oxidation (PROX) Reaction, covering chemical kinetics and heat/mass transfer phenomena that occur in a shell and tube system, to be used in a beta 5kWe hydrogen generator for Polymer Electrolyte Fuel Cells (PEFCs). The critical issue in the PROX reactor design is to achieve temperature control along the catalyst bed, because poor selectivities primarily result from excess reactor temperature. Aim of the model is to investigate the effects of the reactor dimensions on process performance, in order to obtain high CO conversion and high selectivity with respect to the undesired H2 oxidation. The CO removal from simulated reformate was examined, by evaluating the temperature and the gas concentration profiles along the reactor. The sensitivity analysis showed that the overall performance is strongly dependent upon the geometrical configurations examined. [Copyright &y& Elsevier]

Abstract: This paper covers the research activities performed at the CNR Institute for Advanced Energy Technologies “Nicola Giordano”, aimed at developing, assembling and testing a hydrogen generator HYGen II, to integrate with a polymer electrolyte fuel cell (PEFC) for stationary applications. The unit can convert light hydrocarbons (methane, propane, LPG, butane), with a nominal hydrogen production of 5Nm3 h−1 and a maximum hydrogen production of 8.5Nm3 h−1. Prototyping design issues and preliminary experimental results, with a proprietary Pt/CeO2 catalyst for the autothermal reforming (ATR) and commercial catalysts for intermediate water gas shift (ITWS) and preferential oxidation (PROX), have been reported. [Copyright &y& Elsevier]

Abstract: This paper deals with a two-dimensional model of a preferential oxidation (PROX) reactor to be used in a beta 5kWe hydrogen generator, named HYGen II, to integrate with polymer electrolyte fuel cells (PEFCs) for residential applications. The reactor geometrical configuration developed is a single-stage multi-tube configuration, in which a cocurrent air flow in the interspace is aimed at improving heat transfer and consequently controlling the temperature of the reactor. The aim of the model is to investigate the process performance of the reactor in order to enhance optimization and control of the PROX unit. The model concerns chemical kinetics and heat and mass transfer phenomena in the reactor. The model plays a key role in overcoming the issues of system design, by evaluating the temperature and the gas concentration profiles in the reactor. The CO removal from simulated reformate was examined with varying inlet temperature. Simulation results showed the strong dependence of the overall performance upon the reactor geometrical configuration. [Copyright &y& Elsevier]

Sorbents for CO 2 capture have been prepared by wet impregnation of a commercial active carbon (Ketjen-black, Akzo Nobel) with two CO 2 -philic compounds, polyethylenimine (PEI) and tetraethylenepentamine (TEPA), respectively. The effects of amine amount (from 10 to 70wt.%), CO 2 concentration in the feed, sorption temperature and gas hourly space velocity on the CO 2 capture performance have been investigated. The sorption capacity has been evaluated using the breakthrough method, with a fixed bed reactor equipped with on line gas chromatograph. The samples have been characterized by N 2 adsorption-desorption, scanning electron microscopy and energy dispersive X-ray (SEM/EDX). A promising CO 2 sorption capacity of 6.90 mmol/g sorbent has been obtained with 70wt.% of supported TEPA at 70°C under a stream containing 80vol% of CO 2 . Sorption tests, carried out with simulated biogas compositions (CH 4 /CO 2 mixtures), have revealed an appreciable CO 2 separation selectivity; stable performance was maintained for 20 adsorption-desorption cycles., (Copyright © 2016. Published by Elsevier B.V.)

Purpose: To evaluate the short-term efficacy and safety of intravitreal bevacizumab for the treatment of retinal angiomatous proliferation., Methods: Seventeen eyes from 16 patients with newly diagnosed retinal angiomatous proliferation underwent intravitreal injections of bevacizumab, 1.25 mg. The patients were scheduled for three monthly bevacizumab injections. Early Treatment of Diabetic Retinopathy Study (ETDRS) best-corrected visual acuity, central macular thickness on optical coherence tomography, and fluorescein angiographic findings were examined before and after treatment. Patients were followed-up for 12 months., Results: The mean best-corrected visual acuity (+/- standard deviation [SD]) at baseline was 39.53 (+/-10.40) letters (Snellen equivalent: 20/42). At 12 months after treatment the mean best-corrected visual acuity (+/-SD) improved significantly (P = 0.0000001) to 47.88 (+/-11.78) letters (Snellen equivalent: 20/28). Best-corrected visual acuity improved 3 ETDRS lines or more in 3 (17.65%) of 17 treated eyes, 14 (82.35%) eyes were stable, and 15 (88.23%) eyes gained 1 or more ETDRS lines. The mean central macular thickness (+/-SD) at baseline was 297 (+/-60.72) microm. At 12 months after treatment, the mean central macular thickness (+/-SD) reduced significantly (P = 0.00001) to 237 (+/-28.80) microm. At the 12-month follow-up, absence of fluorescein leakage was demonstrated in 14 (82%) of 17 treated eyes. No ocular or systemic adverse effects from treatment were encountered., Conclusion: The 12-month results of intravitreal bevacizumab for retinal angiomatous proliferation are very promising with no apparent short-term safety concerns. Treated eyes had a significant functional and anatomical improvement. Further studies will be needed to better determine long-term efficacy and safety.

Purpose: To determine learning effect in healthy patients without perimetric experience, tested with the frequency doubling technology perimetry, with the new model Matrix., Patients and Methods: Frequency doubling technology in the 30-2 threshold mode was performed on 37 healthy subjects. Each subject was tested twice in different sessions. The test always began with the right eye (RE) and continued with the left eye (LE). To evaluate learning effect the results of the REs at the first session were compared with those of the LE. The following parameters were evaluated: foveal threshold (FT), reliability indexes, mean defect (MD), pattern standard deviation (PSD), glaucoma hemifield test (GHT), duration of examination., Results: At the first session the average values of RE were FT=30.81 db, MD=-1 db, PSD=3.01 db, and duration of the examination=383.27 "and of LE were FT=30.73, MD=-0.79 db, PSD=2.97 db, and duration of examination 382.62." At the second session the average values of RE were FT=32.22 db, MD=+0.16 db, PSD 2.75 db, and duration of examination=374.97 db. The reliability was different and the GHT between the RE and LE in the first and second session was also different., Conclusions: A learning effect was observed between the first and the second sessions and the results of the GHT appeared improved. This above all should be taken into account when considering the clinical use of this test to avoid erroneous diagnostic conclusions.

Objective: To determine whether methylene tetrahydrofolate reductase (MTHFR) C677T mutation, factor II G20210A mutation and factor V Leiden are risk factors for retinal vein occlusion (RVO) in patients under fifty years of age., Methods: Comparison of 29 patients, under 50 years old of age, as affected RVO and 62 age matched normal controls. Plasma MTHFR C677T genotype, Factor II G20210A genotype, Factor V Leiden genotype, S protein level, C protein level, APCR presence (Actived Protein C Resistance), homocysteine level and Beta-thromboglobulin level were determined., Results: Seventeen RVO patients and twenty-one controls were heterozygous for the MTHFR C677T mutation. Three RVO patients and twenty-three controls were homozygous for the MTHFR C677T mutation. Three RVO patients and two controls were heterozygous for the factor II G20210A mutation. One control was heterozygous for the factor V Leiden., Conclusions: This study fails to demonstrate that these mutations are risk factors for RVO in patients under fifty years of age.

Purpose: To evaluate intraocular pressure (IOP) variations after automated visual field examination in patients with primary open-angle glaucoma and in healthy subjects., Patients and Methods: Intraocular pressure was measured in 49 patients (94 eyes) with primary open-angle glaucoma and in 13 healthy subjects (26 eyes) before and immediately after automated visual field examination. All patients had stable IOP and were using local medication to treat glaucoma. The visual field test was performed with a Humphrey 630 VF analyzer and the Central 30-2 full-threshold program., Results: Mean IOP increased significantly in glaucomatous patients immediately after automated visual field examination (P < 0.01), and returned to pretest values after 1 hour (P = 0.2). Mean IOP variation was 2.38 (range, -6-11) mm Hg. In 42 (44.68%) glaucomatous eyes, IOP increased more than 2 mm Hg, with a mean increase of 5.5 mm Hg. Elderly glaucoma patients showed a significantly higher IOP rise than younger patients. No significant IOP variation was detected in healthy subjects., Conclusion: Intraocular pressure varied significantly and tended to increase immediately after automated visual field examination in patients with primary open-angle glaucoma. Age seemed to contribute to these IOP changes, but other factors could be involved.