Performance Assessment of Electric Energy Storage (EES) Systems Based on Reversible Solid Oxide Cell

Abstract This paper focuses on the performance assessment of a novel and efficient EES (electric energy storage) system based on ReSOC (reversible solid oxide cell) technology. The ReSOC is an electrochemical energy conversion device working at high temperature (600-1000°C) that can operate reversibly either as a fuel cell (SOFC) or as an electrolyzer (SOEC). In this study, a ReSOC unit fed by mixtures of CH4, CO, H2O and H2 is proposed and analyzed. In particular, in the SOFC mode, where electricity is generated, the reactant gas, mainly formed by CH4 and H2, is converted into a mixture of H2O and CO2. The exhausts from the SOFC are used as the reactant gas for the SOEC operation. During the electrolysis process, CH4 can be also produced thanks to the methanation reaction that, under proper operating conditions, occurs at the cathode of the solid oxide cell. The ReSOC unit behavior is investigated by developing a thermo-electrochemical model, able to predict its performance (i.e. roundtrip efficiency, polarization curve, thermally self-sustaining conditions) under different operating conditions. The ReSOC model, built with a modular architecture, is performed through thermodynamic, thermochemical and electrochemical sub-models taking into account mass and energy balances, chemical reactions (reforming, shifting reactions and methanation) and electro-chemical relationships. Available literature data have been used for the model validation and a calibration procedure has been performed in order to evaluate the best fitting values for the model parameters. Furthermore, in order to estimate the thermoneutral conditions in SOEC operating mode, the ReSOC thermal behavior has been analyzed under different operating temperatures. Results pointed out that, by feeding the cell with a syngas mixture, the reforming reaction (in the SOFC mode) and the methanation reaction (in the SOEC mode) allow to simplify the cell thermal management. Moreover, the best performance in terms of stack roundtrip efficiency (about 70%), can be reached operating the ReSOC at low temperature (700°C)

Conventional and Advanced Biomass Gasification Power Plants Designed for Cogeneration Purpose

Abstract In this paper conventional and advanced biomass gasification power plants designed for small cogeneration application are defined. The CHP plants consist of a gasification unit, that employs a downdraft gasifier, and a power unit based on a microturbine in the case of conventional configuration, and on a solid oxide fuel cell module, in the case of advanced configuration. The plants are sized to supply about 100 kW of electrical power. In order to investigate and to analyze the performances of the two plant configurations, in terms of thermal and electrical efficiencies, numerical models have been developed by using thermochemical and thermodynamic codes

The use of knee mega-prosthesis for the management of distal femoral fractures: A systematic review

Introduction: Distal femur fractures (DFFs) are unusual and difficult to deal, especially in elderly patients. A consensus about a gold-standard treatment has not been reached yet. Available options include both conservative and surgical management. In elderly patients a prosthetic replacement could be a valid treatment option. Literature is lacking about the use of mega-prosthesis in this type of fractures. The purpose of the present systematic review is to examine which fracture, both acute and chronic, involving distal femur should be treated by using a mega-prosthesis. Materials and Methods: Studies were identified by searching electronic databases. All studies that enrolled people of any age affected by a DFFs treated by using a megaprosthesis were included. Primary outcomes of the present reviews were: ROM, functional assessment and complications. Two review authors independently selected eligible trials. Disagreements at any stage were resolved by consensus or a third party adjudication. Descriptive statics was used to summarize the data. Results: Thirteen article were finally included in the review. One hundred-four patients were treated with knee megaprosthesis. Three categories of patients were identified: 29 patients were affected by supracondylar femur fracture; 51 patients occurred with a periprosthetic fracture; 24 patients suffered a non-union of a previous supracondylar fracture. The follow-up varied between 6 months to 58 months. All studies showed good results in terms of improving quality of life, resuming activities of daily living (ADLs), early mobilization, ROM, shorter hospital stay. Although not frequent, the only reported complications were infection and aseptic loosening. Discussion: The present review showed that the use of knee megaprosthetic implants could represent a valid treatment option aiming to reduce patients’ immobilitazion and hospital stay. Good clinical outcomes with low rate of complications were reported by all included studies. Literature is lacking about long-term outcomes and complications. Moreover studies comparing knee prostheses and other types of surgical treatment (intramedullary nails, plate fixation system) are needed. Conclusions: Megaprosthesis represent a viable treatment option in patients affected by DFFs (either acute, periprostethic or non-union) because they allow immediate weight-bearing, shorter hospital stay, a fast recovery of knee function and ADLs

Who Did the Arthroplasty? Hip Fracture Surgery Reoperation Rates are Not Affected by Type of Training-An Analysis of the HEALTH Database

OBJECTIVES: This study compares outcomes for patients with displaced femoral neck fractures undergoing hemiarthroplasty (HA) or total hip arthroplasty (THA) by surgeons of different fellowship training. DESIGN: Retrospective review of HEALTH trial data. SETTING: Eighty clinical sites across 10 countries. PATIENTS/PARTICIPANTS: One thousand four hundred forty-one patients ≥50 years with low-energy hip fractures requiring surgical intervention. INTERVENTION: Patients were randomized to either HA or THA groups in the initial data set. Surgeons' fellowship training was ascertained retrospectively, and outcomes were compared. MAIN OUTCOME MEASUREMENTS: The main outcome was an unplanned secondary procedure at 24 months. Secondary outcomes included death, serious adverse events, prosthetic joint infection (PJI), dislocation, discharge disposition, an

New national and regional Annex I Habitat records: from #102 to #122*

New Italian data on the distribution of the Annex I Habitats are reported in this contribution. Specifically, 9 new occurrences in Natura 2000 sites are presented and 34 new cells are added in the EEA 10 km × 10 km reference grid. The new data refer to the Italian administrative regions of Abruzzo, Apulia, Calabria, Latium, Lombardy, Marche, Sardinia, Sicily, Tuscany and Umbria

New national and regional Annex I Habitat records: From #45 to #59

New Italian data on the distribution of Annex I Habitats are reported in this contribution. Specifically, 8 new occurrences in Natura 2000 sites are presented and 27 new cells are added in the EEA 10 km × 10 km reference grid. The new data refer to the Italian administrative regions of Apulia, Campania, Calabria, Lazio, Tuscany, Umbria, Sardinia, and Sicily

Notulae to the Italian alien vascular flora: 12

In this contribution, new data concerning the distribution of vascular flora alien to Italy are presented. It includes new records, confirmations, exclusions, and status changes for Italy or for Italian administrative regions. Nomenclatural and distribution updates published elsewhere are provided as Suppl. material 1